Nts'etsopele ea ts'ebetso e phahameng, li-sensor tsa khase tse nkehang habonolo le tse nyane li ntse li tsoela pele ho tsepamisa maikutlo litabeng tsa tlhahlobo ea tikoloho, ts'ireletso, tlhahlobo ea bongaka le temo.Har'a lisebelisoa tse fapaneng tsa ho lemoha, li-sensors tsa chemo-resistive gas tsa metal-oxide-semiconductor (MOS) ke khetho e tsebahalang haholo bakeng sa lits'ebetso tsa khoebo ka lebaka la botsitso ba tsona bo phahameng, theko e tlase, le kutlo e phahameng.E 'ngoe ea mekhoa ea bohlokoa ka ho fetisisa ea ho ntlafatsa ts'ebetso ea sensor ke ho theha li-heterojunctions tse thehiloeng ho MOS tse nang le nanosized (hetero-nanostructured MOS) ho tloha MOS nanomaterials.Leha ho le joalo, mochine oa kutlo oa sensor ea MOS ea heteronanostructured o fapane le oa mochine o le mong oa khase ea MOS, kaha o rarahane haholo.Ts'ebetso ea li-sensor e angoa ke likarolo tse fapaneng, ho kenyeletsoa sebopeho sa 'mele le lik'hemik'hale tsa thepa e bobebe (joalo ka boholo ba lijo-thollo, bofokoli, le likheo tsa oksijene), mocheso oa ts'ebetso le sebopeho sa sesebelisoa.Tlhahlobo ena e fana ka maikutlo a 'maloa bakeng sa ho rala li-sensor tsa khase tse sebetsang hantle ka ho sekaseka mokhoa oa ho utloa oa li-sensor tsa MOS tse nang le nanostructured.Ho phaella moo, ho buuoa ka tšusumetso ea sebopeho sa geometri sa sesebelisoa, se khethiloeng ke kamano pakeng tsa lisebelisoa tse hlokolosi le electrode e sebetsang.Ho ithuta boits'oaro ba sensor ka mokhoa o hlophisehileng, sengoloa sena se hlahisa le ho tšohla mokhoa o akaretsang oa pono ea meaho e meraro e tloaelehileng ea lisebelisoa tse thehiloeng ho lisebelisoa tse fapaneng tsa sebopeho sa heteronano.Kakaretso ena e tla sebetsa e le tataiso bakeng sa babali ba kamoso ba ithutang mekhoa e hlokolosi ea lisensara tsa khase le ho nts'etsapele lisensara tsa khase tse sebetsang hantle.
Tšilafalo ea moea ke bothata bo ntseng bo eketseha bo tebileng le bothata bo tebileng ba tikoloho lefatšeng ka bophara bo sokelang boiketlo ba batho le libōpuoa tse phelang.Ho hema lintho tse silafatsang tsa khase ho ka baka mathata a mangata a bophelo bo botle joalo ka lefu la ho hema, mofetše oa matšoafo, leukemia esita le lefu le tlang pele ho nako1,2,3,4.Ho tloha ka 2012 ho ea ho 2016, ho tlalehoa hore batho ba limilione ba shoele ka lebaka la tšilafalo ea moea, 'me selemo se seng le se seng, batho ba limilione tse likete ba ne ba pepesehetse moea o fokolang5.Ka hona, ke habohlokoa ho hlahisa li-sensor tsa khase tse nkehang habonolo le tse nyenyane tse ka fanang ka maikutlo a nako ea sebele le ts'ebetso e phahameng ea ho lemoha (mohlala, sensitivity, selectivity, botsitso, le likarabo le linako tsa ho hlaphoheloa).Ntle le tlhahlobo ea tikoloho, li-sensor tsa khase li bapala karolo ea bohlokoa ho polokeho6,7,8, tlhahlobo ea bongaka9,10, aquaculture11 le masimo a mang12.
Ho fihlela joale, li-sensor tse ngata tse nkehang tsa khase tse thehiloeng ho mekhoa e fapaneng ea ho lemoha li kentsoe, tse kang optical13,14,15,16,17,18, electrochemical19,20,21,22 le lik'hemik'hale tse thibelang lik'hemik'hale23,24.Har'a tsona, li-sensors tse hanyetsanang tsa lik'hemik'hale tsa metal-oxide-semiconductor (MOS) ke tsona tse ratoang ka ho fetisisa lits'ebetsong tsa khoebo ka lebaka la botsitso ba tsona bo phahameng le theko e tlaase25,26.Khatiso e silafetseng e ka khethoa feela ka ho lemoha phetoho ea khanyetso ea MOS.Mathoasong a lilemo tsa bo-1960, ho ile ha tlalehoa lisebelisoa tsa pele tsa khase tse thibelang chemo tse thehiloeng lifiliming tse tšesaane tsa ZnO, tse hlahisang thahasello e kholo tšimong ea ho lemoha khase27,28.Kajeno, li-MOS tse ngata tse fapaneng li sebelisoa e le lisebelisoa tse thibelang khase, 'me li ka aroloa ka mekhahlelo e' meli ho latela thepa ea bona ea 'mele: MOS ea mofuta oa n-mofuta o nang le lielektrone e le tse tsamaisang litefiso tse ngata le MOS ea mofuta oa p e nang le masoba joalo ka bajari ba bangata ba tjhajang.lefisa bajari.Ka kakaretso, mofuta oa p MOS ha o ratoe haholo ho feta oa mofuta oa n-MOS hobane karabelo ea inductive ea mofuta oa p-MOS (Sp) e lekana le motso oa lisekoere oa mofuta oa n-MOS (\(S_p = \sqrt { S_n}\ )) ka maikutlo a tšoanang (mohlala, sebopeho se tšoanang sa morphological le phetoho e tšoanang ea ho kobeha ha lihlopha moeeng) 29,30.Leha ho le joalo, li-sensor tsa MOS tse nang le motheo o le mong li ntse li tobana le mathata a kang moeli o sa lekaneng oa ho lemoha, kutlo e tlaase le ho khetha lits'ebetsong tse sebetsang.Litaba tsa khetho li ka rarolloa ho isa bohōleng bo itseng ka ho theha lihlopha tsa li-sensor (tse bitsoang "linko tsa elektroniki") le ho kenyelletsa li-algorithms tsa tlhahlobo ea computational joalo ka koetliso ea vector quantization (LVQ), principal component analysis (PCA), le partial least squares (PLS) analysis31 , 32, 33, 34, 35. Ho feta moo, tlhahiso ea li-low-dimensional MOS32,36,37,38,39 (mohlala, one-dimensional (1D), 0D le 2D nanomaterials), hammoho le tšebeliso ea li-nanomaterials tse ling ( mohlala MOS40,41,42 , noble metal nanoparticles (NPs))43,44, carbon nanomaterials45,46 and conductive polymers47,48) ho etsa nanoscale heterojunctions (ke hore, heteronanostructured MOS) ke mekhoa e meng e ratoang ho rarolla mathata a ka holimo.Ha ho bapisoa le lifilimi tsa setso tsa MOS tse teteaneng, MOS e nang le mahlakore a tlaase e nang le sebaka se phahameng se phahameng se ka fana ka libaka tse sebetsang haholoanyane bakeng sa khase le ho tsamaisa khase36,37,49.Ho phaella moo, moralo oa li-heteronanostructures tse thehiloeng ho MOS li ka tsoela pele ho tsamaisa lipalangoang tsa lipalangoang ho heterointerface, e leng se etsang hore ho be le liphetoho tse kholo tsa ho hanyetsa ka lebaka la mesebetsi e fapaneng ea ts'ebetso50,51,52.Ho phaella moo, tse ling tsa liphello tsa lik'hemik'hale (mohlala, ts'ebetso ea catalytic le synergistic surface reactions) e hlahang ha ho etsoa moralo oa MOS heteronanostructures e ka boela ea ntlafatsa ts'ebetso ea sensor.50,53,54 Le hoja ho qapa le ho etsa MOS heteronanostructures e ka ba mokhoa o tšepisang oa ho ntlafatsa. ts'ebetso ea sensor, li-sensor tsa morao-rao tse thibelang chemo hangata li sebelisa liteko le liphoso, tse jang nako ebile ha li sebetse hantle.Ka hona, ke habohlokoa ho utloisisa mochine oa kutlo oa li-sensors tsa khase tse thehiloeng ho MOS kaha li ka tataisa moralo oa li-sensor tse sebetsang hantle.
Lilemong tsa morao tjena, li-sensor tsa khase tsa MOS li tsoetse pele ka potlako 'me litlaleho tse ling li hatisitsoe ho MOS nanostructures55,56,57, li-sensors tsa khase ea mocheso oa kamore58,59, lisebelisoa tse khethehileng tsa MOS sensor60,61,62 le lisebelisoa tse khethehileng tsa khase63.Pampiri ea tlhahlobo ho Litlhahlobo tse ling e shebana le ho hlakisa mokhoa oa ho utloa oa lisele tsa khase tse thehiloeng ho thepa ea tlhaho ea 'mele le ea lik'hemik'hale tsa MOS, ho kenyelletsa le karolo ea likheo tsa oksijene 64, karolo ea heteronanostructures 55, 65 le ho fetisetsa tefiso ho li-heterointerfaces 66. Ho phaella moo , likarolo tse ling tse ngata li ama ts'ebetso ea sensor, ho kenyelletsa le heterostructure, boholo ba lijo-thollo, mocheso oa ts'ebetso, bofokoli ba sekoli, likheo tsa oksijene, esita le lifofane tse bulehileng tsa kristale tsa lintho tse bonolo25,67,68,69,70,71.72, 73. Leha ho le joalo, sebopeho sa (seo se sa boleloang ka seoelo) sa geometri sa sesebelisoa, se khethiloeng ke kamano pakeng tsa lisebelisoa tsa ho utloa le electrode e sebetsang, e boetse e ama haholo kutloisiso ea sensor74,75,76 (bona karolo ea 3 bakeng sa lintlha tse ling) .Ka mohlala, Kumar et al.77 e tlalehile li-sensor tse peli tsa khase tse ipapisitseng le thepa e ts'oanang (mohlala, li-sensor tsa khase tse mekhahlelo e 'meli tse thehiloeng ho TiO2@NiO le NiO@TiO2) mme e hlokometse liphetoho tse fapaneng tsa ho hanyetsa khase ea NH3 ka lebaka la lijeometri tse fapaneng tsa sesebelisoa.Ka hona, ha u hlahloba mochine oa ho lemoha khase, ke habohlokoa ho ela hloko sebopeho sa sesebelisoa.Tlhahlobisong ena, bangoli ba tsepamisitse maikutlo mekhoeng ea ho lemoha e thehiloeng ho MOS bakeng sa mefuta e fapaneng ea li-nanostructures le lisebelisoa tsa lisebelisoa.Re lumela hore tlhahlobo ena e ka sebetsa e le tataiso bakeng sa babali ba lakatsang ho utloisisa le ho hlahloba mekhoa ea ho lemoha khase 'me e ka kenya letsoho ho nts'etsopele ea li-sensor tsa khase tse phahameng tsa nakong e tlang.
Ka feiga.1a e bonts'a mohlala oa mantlha oa mochini o utloang khase o thehiloeng ho MOS e le 'ngoe.Ha mocheso o ntse o phahama, ho kenngoa ha limolek'hule tsa oksijene (O2) holim'a MOS ho tla hohela lielektrone tse tsoang ho MOS le ho theha mefuta ea anionic (e kang O2- le O-).Joale, electron depletion layer (EDL) bakeng sa MOS ea mofuta oa n kapa lesela la ho bokella lesoba (HAL) bakeng sa mofuta oa p-mofuta oa MOS joale e thehoa holim'a MOS 15, 23, 78. Tšebelisano pakeng tsa O2 le MOS e etsa hore sehlopha sa conduction sa MOS se kobehele holimo ebe se etsa tšitiso e ka bang teng.Ka mor'a moo, ha kutlo e pepesehetse khase e lebisitsoeng, khase e adsorbed holim'a MOS e sebetsana le mefuta ea oksijene ea ionic, e ka hohelang li-electrone (khase ea oxidizing) kapa ho fana ka li-electrone (ho fokotsa khase).Ho fetisoa ha elektronike pakeng tsa khase e lebisitsoeng le MOS ho ka fetola bophara ba EDL kapa HAL30,81 ho fella ka phetoho ea ho hanyetsa ka kakaretso ea sensor ea MOS.Ka mohlala, bakeng sa khase e fokotsang, li-electrone li tla fetisoa ho tloha khase e fokotsang ho ea ho MOS ea mofuta oa n, e leng se etsang hore ho be le EDL e tlaase le ho hanyetsa ho tlaase, e leng se bitsoang n-type sensor behaviour.Ka lehlakoreng le leng, ha MOS ea mofuta oa p e pepesehetse khase e fokotsang e khethollang mokhoa oa ho itšoara ka mofuta oa p, HAL e fokotseha 'me khanyetso e eketseha ka lebaka la monehelo oa elektronike.Bakeng sa likhase tsa oxidizing, karabelo ea sensor e fapane le ea ho fokotsa likhase.
Mekhoa ea mantlha ea ho lemoha bakeng sa mofuta oa n-mofuta le p-mofuta oa MOS bakeng sa ho fokotsa le likhase tsa oxidizing b Lintlha tsa bohlokoa le thepa ea physico-chemical kapa thepa e amehang ho li-sensor tsa khase ea semiconductor 89
Ntle le mokhoa oa mantlha oa ho lemoha, mekhoa ea ho lemoha khase e sebelisoang ho li-sensor tsa khase e rarahane haholo.Ka mohlala, tšebeliso ea sebele ea sensor ea khase e tlameha ho finyella litlhoko tse ngata (tse kang kutloisiso, khetho, le botsitso) ho itšetlehile ka litlhoko tsa mosebedisi.Litlhoko tsena li amana haufi-ufi le thepa ea 'mele le ea lik'hemik'hale ea thepa e hlokolosi.Ka mohlala, Xu et al.71 o bontšitse hore li-sensor tse thehiloeng ho SnO2 li finyella kutloisiso e phahameng ka ho fetisisa ha bophara ba kristale (d) bo lekana kapa bo ka tlaase ho habeli bolelele ba Debye (λD) ba SnO271.Ha d ≤ 2λD, SnO2 e felile ka ho feletseng ka mor'a ho phatlalatsoa ha limolek'hule tsa O2, 'me karabelo ea sensor ho khase e fokotsang e phahame haholo.Ntle le moo, likarolo tse ling tse fapaneng li ka ama ts'ebetso ea sensor, ho kenyelletsa mocheso oa ts'ebetso, bofokoli ba kristale, esita le lifofane tse pepesitsoeng tsa kristale tsa lisebelisoa tsa kutlo.Haholo-holo, tšusumetso ea mocheso o sebetsang o hlalosoa ke tlhōlisano e ka bang teng pakeng tsa litekanyetso tsa adsorption le desorption ea khase e lebisitsoeng, hammoho le ts'ebetso ea holim'a metsi pakeng tsa limolek'hule tsa khase ea adsorbed le likaroloana tsa oksijene4,82.Phello ea bofokoli ba kristale e amana haholo le litaba tsa likheo tsa oksijene [83, 84].Ts'ebetso ea sensor e ka boela ea angoa ke reactivity e fapaneng ea lifahleho tse bulehileng tsa kristale67,85,86,87.Lifofane tse bulehileng tsa kristale tse nang le letsoalo le tlase li senola li-cations tsa tšepe tse sa hokahaneng tse nang le matla a holimo, a khothalletsang ho bapatsa le ho sebetsa hape88.Letlapa la 1 le thathamisa lintlha tse 'maloa tsa bohlokoa le mekhoa ea bona ea maikutlo e ntlafalitsoeng.Ka hona, ka ho fetola lisebelisoa tsena tsa lisebelisoa, ts'ebetso ea ho lemoha e ka ntlafatsoa, 'me ke habohlokoa ho fumana lintlha tsa bohlokoa tse amang ts'ebetso ea sensor.
Yamazoe89 le Shimanoe et al.68,71 ba ile ba etsa liphuputso tse 'maloa ka mokhoa oa theory of sensor perception' me ba etsa tlhahiso ea lintlha tse tharo tse ikemetseng tse susumetsang ts'ebetso ea sensor, haholo-holo mosebetsi oa ho amohela, mosebetsi oa transducer, le thuso (setšoantšo sa 1b)..Mosebetsi oa ho amohela o bolela bokhoni ba sebaka sa MOS ho sebelisana le limolek'hule tsa khase.Mosebetsi ona o amana haufi-ufi le thepa ea lik'hemik'hale tsa MOS 'me e ka ntlafatsoa haholo ka ho hlahisa ba amohelang linaheng tse ling (mohlala, NPs ea tšepe le MOS e meng).Mosebetsi oa transducer o bolela bokhoni ba ho fetola karabelo pakeng tsa khase le bokaholimo ba MOS hore e be lets'oao la motlakase le laoloang ke meeli ea lijo-thollo tsa MOS.Ka hona, ts'ebetso ea kutlo e ameha haholo ke boholo ba likaroloana tsa MOC le bongata ba li-receptor tsa kantle ho naha.Katoch et al.90 ba tlaleha hore ho fokotsa boholo ba lijo-thollo tsa ZnO-SnO2 nanofibrils ho entse hore ho thehoe li-heterojunctions tse ngata le ho eketseha ha kutlo ea kutlo, e lumellanang le ts'ebetso ea transducer.Wang et al.91 o ile a bapisa mefuta e sa tšoaneng ea lijo-thollo tsa Zn2GeO4 'me a bontša keketseho ea 6.5 ea kutloisiso ea kutlo ka mor'a ho hlahisa meeli ea lijo-thollo.Utility ke ntlha e 'ngoe ea bohlokoa ea ts'ebetso ea sensor e hlalosang boteng ba khase ho sebopeho sa kahare sa MOS.Haeba limolek'hule tsa khase li sa khone ho kenella le ho itšoara ka MOS e ka hare, kutloisiso ea sensor e tla fokotseha.Molemo o amana haufi-ufi le botebo ba phallo ea khase e itseng, e itšetlehileng ka boholo ba pore ea thepa ea kutlo.Sakai et al.92 e ile ea etsa mohlala oa kutlo ea sensor ho likhase tsa flue mme ea fumana hore boima ba limolek'hule tsa khase le radius ea pore ea membrane ea sensor e ama kutlo ea kutlo ho botebo bo fapaneng ba phallo ea khase ka har'a membrane ea sensor.Puisano e ka holimo e bontša hore li-sensor tsa khase tse sebetsang hantle li ka ntlafatsoa ka ho leka-lekanya le ho ntlafatsa ts'ebetso ea li-receptor, mosebetsi oa transducer, le ts'ebeliso.
Mosebetsi o ka holimo o hlakisa mokhoa oa motheo oa maikutlo oa MOS o le mong 'me o tšohla lintlha tse' maloa tse amang ts'ebetso ea MOS.Ntle le lintlha tsena, li-sensor tsa khase tse thehiloeng ho heterostructures li ka ntlafatsa ts'ebetso ea sensor ka ho ntlafatsa haholo mesebetsi ea sensor le receptor.Ntle le moo, li-heteronanostructures li ka ntlafatsa ts'ebetso ea sensor ka ho ntlafatsa karabelo ea catalytic, ho laola phetiso ea litefiso, le ho theha libaka tse ling tsa papatso.Ho fihlela joale, li-sensor tse ngata tsa khase tse thehiloeng ho MOS heteronanostructures li 'nile tsa ithutoa ho buisana ka mekhoa ea ho ntlafatsa maikutlo95,96,97.Miller le ba bang.55 e akaretsa mekhoa e 'maloa e ka ntlafatsang kutloisiso ea li-heteronanostructures, ho kenyelletsa le ho itšetlehile ka holimo, ho itšetlehile ka sebopeho, le ho itšetlehile ka sebopeho.Har'a tsona, mochine oa amplification o itšetlehileng ka sebopeho o rarahane haholo hore o ka koahela litšebelisano tsohle tsa li-interface ka khopolo e le 'ngoe, kaha li-sensor tse fapa-fapaneng tse itšetlehileng ka thepa ea heteronanostructured (mohlala, nn-heterojunction, pn-heterojunction, pp-heterojunction, joalo-joalo) e ka sebelisoa. .Schottky knot).Ka tloaelo, li-sensor tse thehiloeng ho MOS tse thehiloeng ho heteronanostructured li lula li kenyelletsa mekhoa e 'meli kapa ho feta ea sensor98,99,100.Tšusumetso ea synergistic ea mekhoa ena ea amplification e ka ntlafatsa kamohelo le ts'ebetso ea matšoao a sensor.Kahoo, ho bohlokoa ho utloisisa mokhoa oa ho lemoha ha li-sensor tse thehiloeng ho lisebelisoa tse fapaneng tsa nanostructured ho thusa bafuputsi ho etsa li-sensor tsa khase tse tlase ho ea holimo ho latela litlhoko tsa bona.Ho phaella moo, sebopeho sa geometri sa sesebelisoa se ka boela sa ama haholo kutloisiso ea kutlo ea 74, 75, 76. E le ho hlahloba ka mokhoa o hlophisitsoeng boitšoaro ba mochine, mekhoa ea ho lemoha ea lisebelisoa tse tharo tse thehiloeng ho lisebelisoa tse fapaneng tsa heteronanostructured li tla hlahisoa. le ho tšohloa ka tlase.
Ka nts'etsopele e potlakileng ea li-sensor tsa khase tse thehiloeng ho MOS, MOS e fapaneng e nang le hetero-nanostructured e hlahisitsoe.Ho fetisoa ha tefiso ho heterointerface ho itšetlehile ka maemo a fapaneng a Fermi (Ef) a likaroloana.Ha li-heterointerface, li-electrone li tloha ka lehlakoreng le leng ka Ef e khōloanyane ho ea ka lehlakoreng le leng ka Ef e nyenyane ho fihlela maemo a bona a Fermi a fihla ho lekana, le masoba, ka tsela e fapaneng.Joale bajari ba heterointerface ba fokotsehile 'me ba etsa lera le fokolang.Hang ha sensor e pepesehetse khase e lebisitsoeng, mahloriso a MOS a nang le heteronanostructured a fetoha, joalo ka bophahamo ba mokoallo, kahoo a matlafatsa lets'oao la ho lemoha.Ho feta moo, mekhoa e fapaneng ea ho etsa li-heteronanostructures e lebisa likamanong tse fapaneng pakeng tsa lisebelisoa le li-electrode, tse lebisang ho li-geometri tse fapaneng tsa lisebelisoa le mekhoa e fapaneng ea ho lemoha.Tlhahlobisong ena, re sisinya mekhoa e meraro ea lisebelisoa tsa geometri mme re buisane ka mokhoa oa ho utloa bakeng sa sebopeho ka seng.
Le hoja li-heterojunctions li phetha karolo ea bohlokoa haholo ts'ebetsong ea ho lemoha khase, mochine oa geometry oa mochine oohle o ka boela oa susumetsa haholo boitšoaro ba ho lemoha, kaha sebaka sa mochine oa ho khanna oa sensor se itšetlehile haholo ka geometry ea mochine.Li-geometri tse tharo tse tloaelehileng tsa lisebelisoa tsa MOS tsa heterojunction li tšohloa mona, joalokaha ho bontšitsoe setšoantšong sa 2. Mofuteng oa pele, likhokahano tse peli tsa MOS li aroloa ka mokhoa o sa reroang pakeng tsa li-electrode tse peli, 'me sebaka sa mocha oa conductive se khethoa ke MOS e kholo, ea bobeli ke ho thehoa ha li-nanostructures tse sa tšoaneng ho tloha MOS e fapaneng, ha MOS e le 'ngoe feela e hokahane le electrode.electrode e hokahane, ebe mocha oa conductive o atisa ho ba ka hare ho MOS mme o amana ka ho toba le electrode.Mofuteng oa boraro, lisebelisoa tse peli li khomaretsoe ho li-electrode tse peli ka thoko, li tataisa sesebelisoa ka heterojunction e entsoeng pakeng tsa lisebelisoa tse peli.
Khokahano pakeng tsa metsoako (mohlala, "SnO2-NiO") e bontša hore likarolo tse peli li tsoakane feela (mofuta oa I).Letšoao la "@" lipakeng tsa likhokahano tse peli (mohlala, "SnO2@NiO") e bonts'a hore thepa ea scaffold (NiO) e khabisitsoe ka SnO2 bakeng sa sebopeho sa sensor ea mofuta oa II.Slash (mohlala, "NiO/SnO2") e bonts'a moralo oa sensor ea mofuta oa III.
Bakeng sa lisebelisoa tsa khase tse thehiloeng ho metsoako ea MOS, likarolo tse peli tsa MOS li aroloa ka mokhoa o sa reroang pakeng tsa li-electrode.Ho 'nile ha etsoa mekhoa e mengata ea ho qapa ho lokisa metsoako ea MOS, ho akarelletsa le sol-gel, coprecipitation, hydrothermal, electrospinning, le mekhoa ea ho kopanya mechine98,102,103,104.Haufinyane tjena, li-metal-organic frameworks (MOFs), sehlopha sa lisebelisoa tse entsoeng ka kristale tse nang le porous tse entsoeng ka litsi tsa tšepe le li-organic linkers, li 'nile tsa sebelisoa e le li-template bakeng sa ho etsoa ha li-composites tsa MOS tse porous105,106,107,108.Ke habohlokoa ho hlokomela hore le hoja peresente ea metsoako ea MOS e tšoana, litšoaneleho tsa kutlo li ka fapana haholo ha li sebelisa mekhoa e fapaneng ea tlhahiso.109,110 Ka mohlala, Gao et al.109 e entse li-sensor tse peli tse thehiloeng ho lihlopha tsa MoO3 ± SnO2 tse nang le tekanyo e tšoanang ea athomo. ( Mo:Sn = 1: 1.9) mme a fumana hore mekhoa e fapaneng ea ho etsa masela e lebisa tlhokomelong e fapaneng.Shaposhnik et al.110 e tlaleha hore karabelo ea co-precipitated SnO2-TiO2 ho gaseous H2 e fapane le ea lisebelisoa tse tsoakiloeng ka mochini, esita le ka tekanyo e tšoanang ea Sn/Ti.Phapang ena e hlaha hobane kamano pakeng tsa MOP le MOP crystallite boholo bo fapana ka mekhoa e fapaneng ea ho kopanya109,110.Ha boholo ba lijo-thollo le sebōpeho li lumellana ho latela boholo ba bafani le mofuta oa semiconductor, karabo e lokela ho lula e tšoana haeba geometry ea ho kopana e sa fetohe 110.Staerz le al.111 e tlalehile hore litšobotsi tsa ho lemoha tsa SnO2-Cr2O3 core-sheath (CSN) nanofibers le fatše SnO2-Cr2O3 CSNs li ne li batla li tšoana, ho fana ka maikutlo a hore nanofiber morphology ha e fane ka molemo leha e le ofe.
Ntle le mekhoa e fapaneng ea masela, mefuta ea semiconductor ea li-MOSFET tse peli tse fapaneng e boetse e ama kutlo ea kutlo.E ka aroloa hape ka mekhahlelo e 'meli ho latela hore na li-MOSFET tse peli ke tsa mofuta o le mong oa semiconductor (nn kapa pp junction) kapa mefuta e fapaneng (pn junction).Ha li-sensors tsa khase li thehiloe ho lihlopha tsa MOS tsa mofuta o le mong, ka ho fetola tekanyo ea molar ea MOS e 'meli, tšobotsi ea karabo ea sensitivity e lula e sa fetohe,' me kutloisiso ea kutlo e fapana ho ea ka palo ea nn- kapa pp-heterojunctions.Ha karolo e le 'ngoe e le teng ka har'a motsoako (mohlala 0.9 ZnO-0.1 SnO2 kapa 0.1 ZnO-0.9 SnO2), mocha oa conduction o khethoa ke MOS ea ka sehloohong, e bitsoang homojunction conduction channel 92 .Ha likarolo tsa likarolo tse peli li bapisoa, ho nkoa hore mocha oa ho khanna o laoloa ke heterojunction98,102.Yamazoe et al.112,113 e tlalehile hore sebaka sa heterocontact sa likarolo tse peli se ka ntlafatsa haholo kutloisiso ea kutlo hobane mokoallo oa heterojunction o entsoeng ka lebaka la mesebetsi e fapaneng ea ts'ebetso ea likaroloana o ka laola ka katleho ho sisinyeha ha sensor ho pepesehetse li-electrone.Likhase tse fapaneng tsa tikoloho 112,113.Ka feiga.Setšoantšo sa 3a se bontša hore li-sensor tse thehiloeng ho SnO2-ZnO li-fibrous hierarchical structures tse nang le litaba tse fapaneng tsa ZnO (ho tloha ho 0 ho ea ho 10 mol% Zn) li ka lemoha ethanol ka boikhethelo.Har'a bona, mochine o thehiloeng ho SnO2-ZnO fibers (7 mol.% Zn) o bontšitse kutloisiso e phahameng ka ho fetisisa ka lebaka la ho thehoa ha palo e kholo ea li-heterojunctions le ho eketseha ha sebaka se itseng sa holimo, se ileng sa eketsa mosebetsi oa converter le ho ntlafatsa. kutlo 90 Leha ho le joalo, ka keketseho e 'ngoe ea litaba tsa ZnO ho 10 mol.%, motsoako oa microstructure SnO2-ZnO o ka koahela libaka tsa ts'ebetso ea holim'a metsi le ho fokotsa kutlo85.Mokhoa o ts'oanang o boetse o hlokomeloa bakeng sa li-sensor tse thehiloeng ho NiO-NiFe2O4 pp heterojunction composite le likarolo tse fapaneng tsa Fe / Ni (setšoantšo sa 3b) 114.
Litšoantšo tsa SEM tsa SnO2-ZnO fibers (7 mol.% Zn) le karabo ea sensor ho likhase tse sa tšoaneng tse nang le mahloriso a 100 ppm ho 260 ° C;54b Likarabo tsa li-sensor tse thehiloeng ho NiO e hloekileng le NiO-NiFe2O4 composite ho 50 ppm ea likhase tse sa tšoaneng, 260 ° C;114 ( c) Setšoantšo sa schematic sa palo ea li-node ho xSnO2-(1-x) Co3O4 sebopeho le ho hanyetsa ho lumellanang le maikutlo a maikutlo a xSnO2-(1-x) Co3O4 sebopeho ka 10 ppm CO, acetone, C6H6 le SO2 khase ho 350 °C ka ho fetola tekanyo ea molar ea Sn/Co 98
Likarolo tsa pn-MOS li bonts'a boitšoaro bo fapaneng ba kutlo ho latela karo-karolelano ea athomo ea MOS115.Ka kakaretso, boitšoaro ba kutlo ba likarolo tsa MOS bo itšetlehile haholo ka hore na MOS e sebetsa e le mocha o ka sehloohong oa ho khanna oa sensor.Ka hona, ho bohlokoa haholo ho khetholla sebopeho sa liperesente le nanostructure ea li-composites.Kim et al.98 o tiisitse qeto ena ka ho kopanya letoto la li-nanofiber tsa xSnO2 ± (1-x) Co3O4 ka electrospinning le ho ithuta thepa ea bona ea kutlo.Ba ile ba hlokomela hore boitšoaro ba SnO2-Co3O4 composite sensor switched ho tloha n-mofuta ho ea p-mofuta ka ho fokotsa peresente ea SnO2 (Fig. 3c)98.Ho phaella moo, li-sensor tse laoloang ke heterojunction (tse thehiloeng ho 0.5 SnO2-0.5 Co3O4) li bontšitse litekanyetso tse phahameng ka ho fetisisa tsa phetisetso ea C6H6 ha li bapisoa le li-sensor tse laolang homojunction (mohlala, li-sensor tse phahameng tsa SnO2 kapa Co3O4).Khanyetso e phahameng ea tlhaho ea sensor e thehiloeng ho 0.5 SnO2-0.5 Co3O4 le bokhoni ba eona bo boholo ba ho fetola ho hanyetsa ka kakaretso ho kenya letsoho ho kutloisiso ea eona e phahameng ka ho fetisisa ho C6H6.Ntle le moo, bofokoli bo sa lumellaneng ba lattice bo tsoang ho SnO2-Co3O4 heterointerfaces bo ka theha libaka tsa papatso tse ikhethileng bakeng sa limolek'hule tsa khase, ka hona tsa ntlafatsa karabelo ea sensor109,116.
Ntle le MOS ea mofuta oa semiconductor, boitšoaro ba ho ama ba likarolo tsa MOS le bona bo ka etsoa ka mokhoa o ikhethileng ho sebelisoa k'hemistri ea MOS-117.Huo et al.117 ba sebelisitse mokhoa o bonolo oa soak-bake ho lokisa metsoako ea Co3O4-SnO2 mme ba fumana hore ka tekanyo ea Co/Sn molar ea 10%, kutlo e bonts'a karabo ea mofuta oa p ho H2 le mofuta oa n-type sensitivity ho H2.karabo.Likarabo tsa sensor ho likhase tsa CO, H2S le NH3 li bontšoa ho Setšoantšo sa 4a117.Likarolong tse tlaase tsa Co / Sn, li-homojunctions tse ngata li theha meeli ea SnO2 ± SnO2 nanograin 'me li bontša likarabo tsa mofuta oa n-mofuta ho H2 (Figs. 4b, c) 115.Ka keketseho ea karolelano ea Co/Sn ho fihla ho 10 mol.%, ho e-na le li-homojunctions tsa SnO2-SnO2, li-heterojunctions tse ngata tsa Co3O4-SnO2 li ile tsa thehoa ka nako e le 'ngoe (setšoantšo sa 4d).Kaha Co3O4 ha e sebetse mabapi le H2, 'me SnO2 e sebetsana ka matla le H2, karabelo ea H2 e nang le mefuta ea oksijene ea ionic e etsahala haholo-holo holim'a SnO2117.Ka hona, li-electrone li fallela SnO2 le Ef SnO2 li fetoha ho ea sehlopheng sa conduction, ha Ef Co3O4 e ntse e sa fetohe.Ka lebaka leo, khanyetso ea sensor e eketseha, e bontšang hore lisebelisoa tse nang le tekanyo e phahameng ea Co / Sn li bontša boitšoaro ba ho lemoha mofuta oa p (setšoantšo sa 4e).Ka lehlakoreng le leng, likhase tsa CO, H2S, le NH3 li itšoara ka mefuta ea oksijene ea ionic holim'a libaka tsa SnO2 le Co3O4, 'me li-electrone li tloha khase ho ea ho sensor, e leng se fellang ka ho fokotseha ha bophahamo ba mokoallo le mofuta oa n-type sensitivity (Fig. 4f)..Boitšoaro bona bo fapaneng ba sensor bo bakoa ke ts'ebetso e fapaneng ea Co3O4 e nang le likhase tse fapaneng, tse ileng tsa tiisoa hape ke Yin et al.118 .Ka ho tšoanang, Katoch et al.119 e bontšitse hore likarolo tsa SnO2-ZnO li na le khetho e ntle le kutlo e phahameng ho H2.Boitšoaro bona bo etsahala hobane liathomo tsa H li ka bapaloa habonolo maemong a O a ZnO ka lebaka la ho kopanya ho matla pakeng tsa s-orbital ea H le p-orbital ea O, e lebisang ho metallization ea ZnO120,121.
a Co/Sn-10% matla a ho hanyetsa likhase bakeng sa likhase tse tloaelehileng tse fokotsang tse kang H2, CO, NH3 le H2S, b, c Co3O4/SnO2 setšoantšo sa mochine o kopanyang oa ho lemoha H2 ka tlaase ho % m.Co/Sn, df Co3O4 Mechanism discovery ea H2 le CO, H2S le NH3 e nang le motsoako o phahameng oa Co/Sn/SnO2
Ka hona, re ka ntlafatsa kutloisiso ea sensor ea mofuta oa I ka ho khetha mekhoa e nepahetseng ea ho etsa masela, ho fokotsa boholo ba lijo-thollo tsa metsoako, le ho ntlafatsa tekanyo ea molar ea metsoako ea MOS.Ntle le moo, kutloisiso e tebileng ea k'hemistri ea lintho tse bobebe e ka ntlafatsa khetho ea sensor.
Mehaho ea sensor ea mofuta oa II ke sebopeho se seng se tsebahalang sa sensor se ka sebelisang lisebelisoa tse fapaneng tse fapaneng tsa nanostructured, ho kenyeletsoa "master" e le 'ngoe le nanomaterial ea bobeli kapa ea boraro.Ka mohlala, lisebelisoa tse nang le likarolo tse le 'ngoe kapa tse peli tse khabisitsoeng ka li-nanoparticles, core-shell (CS) le li-multilayer heteronanostructured thepa li atisa ho sebelisoa mofuteng oa li-sensor tsa mofuta oa II' me li tla tšohloa ka ho qaqileng ka tlase.
Bakeng sa thepa ea pele ea heteronanostructure (e khabisitsoeng ka heteronanostructure), joalokaha ho bontšitsoe setšoantšong sa 2b (1), li-channel conductive tsa sensor li kopantsoe ke lisebelisoa tsa motheo.Ka lebaka la ho thehoa ha li-heterojunctions, li-nanoparticles tse fetotsoeng li ka fana ka libaka tse sebetsang haholoanyane bakeng sa khase ea adsorption kapa desorption, hape e ka sebetsa e le li-catalysts ho ntlafatsa ts'ebetso ea ho lemoha109,122,123,124.Yuan et al.41 ba hlokometse hore ho khabisa li-nanowires tsa WO3 ka CeO2 nanodots ho ka fana ka libaka tse ngata tsa papatso ho CeO2@WO3 heterointerface le holim'a CeO2 le ho hlahisa mefuta e mengata ea oksijene ea chemisorbed bakeng sa ho arabela ka acetone.Gunawan et al.125. Sesebelisoa sa ultra-high sensitivity acetone sensor e thehiloeng ho lehlakoreng le le leng Au @ α-Fe2O3 e 'nile ea etsoa tlhahiso' me ho hlokometsoe hore kutloisiso ea sensor e laoloa ke ts'ebetso ea limolek'hule tsa O2 e le mohloli oa oksijene.Ho ba teng ha Au NPs ho ka sebetsa e le sesosa se khothalletsang ho arohana ha limolek'hule tsa oksijene hore e be oksijene ea lattice bakeng sa oxidation ea acetone.Liphetho tse tšoanang li ile tsa fumanoa ke Choi et al.9 moo sesebelisoa sa Pt se ileng sa sebelisoa ho arola limolek'hule tsa oksijene tse kentsoeng mefuteng ea oksijene ea ionized le ho ntlafatsa karabelo e hlokolosi ho acetone.Ka 2017, sehlopha se le seng sa lipatlisiso se bontšitse hore li-nanoparticles tsa bimetallic li sebetsa hantle haholo ho catalysis ho feta li-nanoparticles tsa tšepe tse le 'ngoe, joalokaha ho bontšitsoe setšoantšong sa 5126. ka karolelano boholo ba ka tlase ho 3 nm.Joale, ho sebelisa mokhoa oa electrospinning, PtM @ WO3 nanofibers e ile ea fumanoa ho eketsa kutloisiso le khetho ho acetone kapa H2S (Fig. 5b-g).Haufinyane tjena, li-catalyst tsa athomo tse le 'ngoe (SACs) li bonts'itse ts'ebetso e ntle haholo ea ts'ebetso lefapheng la catalysis le tlhahlobo ea khase ka lebaka la ts'ebetso e phahameng ea ts'ebeliso ea liathomo le meaho e hlophisitsoeng ea elektroniki127,128.Shin et al.129 e sebelisitse Pt-SA anchored carbon nitride (MCN), SnCl2 le PVP nanosheets e le mehloli ea lik'hemik'hale ho lokisa Pt@MCN@SnO2 likhoele tsa inline bakeng sa ho lemoha khase.Leha ho na le litaba tse tlase haholo tsa Pt@MCN (ho tloha ho 0.13 wt.% ho isa ho 0.68 wt.%), ts'ebetso ea ho lemoha ha gaseous formaldehyde Pt@MCN@SnO2 e phahametse lisampole tse ling tsa litšupiso (pure SnO2, MCN@SnO2 le Pt NPs@ SnO2)..Ts'ebetso ena e ntle haholo ea ho lemoha e ka hlahisoa ka lebaka la katleho e kholo ea athomo ea Pt SA catalyst le bonyane ts'ireletso ea libaka tse sebetsang tsa SnO2129.
Apoferritin-loaded encapsulation mokhoa ho fumana PtM-apo (PtPd, PtRh, PtNi) nanoparticles;thepa e matla ea khase e utloang bohloko ea bd pristine WO3, PtPd@WO3, PtRn@WO3, le Pt-NiO@WO3 nanofibers;e thehiloeng, ka mohlala, ka thepa ea khetho ea PtPd@WO3, PtRn@WO3 le Pt-NiO@WO3 nanofiber sensors ho 1 ppm ea khase e kenang 126.
Ho phaella moo, li-heterojunctions tse entsoeng pakeng tsa lisebelisoa tsa scaffold le nanoparticles li ka boela tsa atleha ho fetola liteishene tsa ho khanna ka mochine oa radial modulation ho ntlafatsa ts'ebetso ea sensor130,131,132.Ka feiga.Setšoantšo sa 6a se bonts'a litšobotsi tsa sensor tsa SnO2 e hloekileng le Cr2O3 @ SnO2 nanowires bakeng sa ho fokotsa le likhase tsa oxidizing le mekhoa e lumellanang ea sensor131.Ha ho bapisoa le li-nanowires tse hloekileng tsa SnO2, karabelo ea Cr2O3 @ SnO2 nanowires ho fokotsa likhase e matlafatsoa haholo, ha karabelo ea likhase tse oxidizing e ntse e mpefala.Liketsahalo tsena li amana haufi-ufi le ho fokotseha ha sebaka sa liteishene tsa conduction tsa SnO2 nanowires ka tataiso ea radial ea pn heterojunction e entsoeng.Ho hanyetsa sensor ho ka hlophisoa habonolo ka ho fetola bophara ba EDL holim'a li-nanowires tse hloekileng tsa SnO2 ka mor'a ho pepesehela likhase tse fokotsang le tsa oxidizing.Leha ho le joalo, bakeng sa Cr2O3 @ SnO2 nanowires, DEL ea pele ea SnO2 nanowires moeeng e eketsehile ha e bapisoa le SnO2 nanowires e hloekileng, 'me mocha oa conduction o hatelloa ka lebaka la ho thehoa ha heterojunction.Ka hona, ha sensor e pepesehetse khase e fokotsang, li-electrone tse koaletsoeng li lokolloa ho SnO2 nanowires 'me EDL e fokotsehile haholo, e leng se hlahisang kutloisiso e phahameng ho feta SnO2 nanowires e hloekileng.Ka lehlakoreng le leng, ha u fetohela khase ea oxidizing, katoloso ea DEL e na le moeli, e bakang kutlo e tlase.Liphetho tse tšoanang tsa karabelo ea kutlo li ile tsa bonoa ke Choi et al., 133 moo SnO2 nanowires e khabisitsoeng ka p-mofuta oa WO3 nanoparticles e bonts'itse karabelo e ntlafalitsoeng haholo ea maikutlo ho fokotsa likhase, athe li-sensor tsa SnO2 tse khabisitsoeng ka n-decorated li ne li ntlafalitse kutloisiso ea likhase tse oxidizing.TiO2 nanoparticles (setšoantšo sa 6b) 133. Sephetho sena se bakoa haholo ke mesebetsi e fapaneng ea mosebetsi oa SnO2 le MOS (TiO2 kapa WO3) nanoparticles.Ka mofuta oa p-type (n-type) nanoparticles, mocha oa ho khanna oa thepa ea moralo (SnO2) o atoloha (kapa likonteraka) ka tataiso ea radial, ebe, tlas'a ketso ea ho fokotsa (kapa oxidation), ho atolosa ho eketsehileng (kapa ho khutsufatsa) ea mocha oa conduction oa SnO2 - rib) ea khase (setšoantšo sa 6b).
Mochine oa ho feto-fetoha ha mahlaseli o hlahisoang ke LF MOS e fetotsoeng.Kakaretso ea likarabo tsa khase ho 10 ppm ho fokotsa le likhase tsa oxidizing tse thehiloeng ho SnO2 e hloekileng le Cr2O3 @ SnO2 nanowires le litšoantšo tse tsamaellanang tsa mochine oa ho lemoha;le merero e tsamaisanang ea WO3@SnO2 nanorods le mokhoa oa ho lemoha133
Ka lisebelisuoa tsa li-bilayer le tsa multilayer heterostructure, mocha oa conduction oa sesebelisoa o laoloa ke lera (hangata lera le ka tlaase) le kopane ka ho toba le li-electrode, 'me heterojunction e entsoeng ka sebopeho sa lihlopha tse peli e ka laola conductivity ea lera le ka tlaase. .Ka hona, ha likhase li kopana le lera le ka holimo, li ka ama haholo liteishene tsa conduction tsa lera le ka tlase le ho hanyetsa 134 ea sesebelisoa.Ka mohlala, Kumar et al.77 e tlalehile boitšoaro bo fapaneng ba TiO2@NiO le NiO@TiO2 mekhahlelo e habeli bakeng sa NH3.Phapang ena e hlaha hobane liteishene tsa conduction tsa li-sensor tse peli li laola ka mekhahlelo ea lisebelisoa tse fapaneng (NiO le TiO2, ka ho latellana), ebe liphapang tsa likanale tse ka tlase tsa conduction li fapane77.
Bilayer kapa multilayer heteronanostructures hangata e hlahisoa ke sputtering, atomic layer deposition (ALD) le centrifugation56,70,134,135,136.Botenya ba filimi le sebaka sa ho ikopanya sa lisebelisoa tse peli li ka laoloa hantle.Lipalo 7a le b li bontša NiO@SnO2 le Ga2O3@WO3 nanofilms tse fumanoeng ka ho sputtering bakeng sa ho lemoha ethanol135,137.Leha ho le joalo, mekhoa ena ka kakaretso e hlahisa lifilimi tse bataletseng, 'me lifilimi tsena tse bataletseng ha li na kutloelo-bohloko ho feta lisebelisoa tsa 3D nanostructured ka lebaka la sebaka sa tsona se tlase se ikhethileng le ho kenella ha khase.Ka hona, leano la karolo ea mokelikeli bakeng sa ho etsa lifilimi tsa bilayer tse nang le lihlopha tse fapaneng le tsona li 'nile tsa etsoa tlhahiso ea ho ntlafatsa ts'ebetso ea maikutlo ka ho eketsa sebaka se itseng sa holimo41,52,138.Zhu et al139 mekhoa e kopantsoeng ea sputtering le hydrothermal ho hlahisa li-nanowires tse laetsoeng haholo tsa ZnO holim'a SnO2 nanowires (ZnO@SnO2 nanowires) bakeng sa ho lemoha H2S (Setšoantšo sa 7c).Karabelo ea eona ho 1 ppm H2S e phahame ka makhetlo a 1.6 ho feta ea sensor e thehiloeng ho sputtered ZnO@SnO2 nanofilms.Liu et al.52 e tlalehile ts'ebetso e phahameng ea H2S sensor e sebelisang mekhoa e 'meli ea ho kenya lik'hemik'hale tsa lik'hemik'hale ho etsa li-nanostructures tsa hierarchical SnO2 @ NiO tse lateloang ke thermal annealing (Fig. 10d).Ha ho bapisoa le lifilimi tse tloaelehileng tsa SnO2 @ NiO bilayer, ts'ebetso ea kutlo ea SnO2 @ NiO ea sebopeho sa hierarchical bilayer e ntlafalitsoe haholo ka lebaka la keketseho ea sebaka se ikhethileng52,137.
Sensor ea khase e habeli e thehiloeng ho MOS.NiO@SnO2 nanofilm bakeng sa ho lemoha ethanol;137b Ga2O3@WO3 nanofilm bakeng sa ho lemoha ethanol;135c e laetsoeng haholo SnO2@ZnO bilayer sebopeho sa maemo bakeng sa ho lemoha H2S;139d SnO2@NiO bilayer sebopeho sa maemo a holimo bakeng sa ho lemoha H2S52.
Ka lisebelisoa tsa mofuta oa II tse thehiloeng ho core-shell heteronanostructures (CSHNs), mochine oa kutlo o rarahane haholo, kaha mechine ea ho khanna ha e felle feela ho khetla e ka hare.Ka bobeli tsela ea ho etsa thepa le botenya (hs) ea sephutheloana li ka tseba sebaka sa liteishene tsa conductive.Ka mohlala, ha u sebelisa mekhoa ea ho kopanya e ka tlase-holimo, likanale tsa conduction hangata li lekanyelitsoe ho mantlha e ka hare, e ts'oanang ka sebopeho ho meaho ea lisebelisoa tse peli kapa tsa multilayer (Fig. 2b (3)) 123, 140, 141, 142, 143. Xu et al.144 e tlalehile mokhoa o ka tlase-holimo oa ho fumana CSHN NiO@α-Fe2O3 le CuO@α-Fe2O3 ka ho kenya lera la NiO kapa CuO NPs ho α-Fe2O3 nanorods moo mocha oa conduction o neng o lekanyelitsoe ke karolo e bohareng.(nanorods α-Fe2O3).Liu et al.142 e boetse e atlehile ho thibela mocha oa conduction karolong e kholo ea CSHN TiO2 @ Si ka ho kenya TiO2 ho lihlopha tse lokiselitsoeng tsa silicon nanowires.Ka hona, boitšoaro ba eona ba ho lemoha (p-type kapa n-type) bo itšetlehile feela ka mofuta oa semiconductor oa silicon nanowire.
Leha ho le joalo, boholo ba li-sensor tse thehiloeng ho CSHN tse tlalehiloeng (setšoantšo sa 2b (4)) li entsoe ka ho fetisetsa phofo ea lisebelisoa tsa CS tse entsoeng holim'a li-chips.Tabeng ena, tsela ea conduction ea sensor e angoa ke botenya ba matlo (hs).Sehlopha sa Kim se ile sa etsa lipatlisiso ka phello ea hs ts'ebetsong ea ho lemoha khase 'me sa etsa tlhahiso ea mokhoa oa ho lemoha100,112,145,146,147,148. Ho lumeloa hore lintlha tse peli li kenya letsoho mochineng oa ho lemoha oa sebopeho sena: (1) ho feto-fetoha ha radial ea EDL ea khetla le (2) phello ea ho tlotsa sebaka sa motlakase (setšoan 8) 145. Bafuputsi ba boletse hore mocha oa ho khanna ea bajari hangata e koaletsoe ho lera la khetla ha hs > λD ea khetla layer145. Ho lumeloa hore lintlha tse peli li kenya letsoho mochineng oa ho lemoha oa sebopeho sena: (1) ho feto-fetoha ha radial ea EDL ea khetla le (2) phello ea ho tlotsa sebaka sa motlakase (setšoan 8) 145. Bafuputsi ba boletse hore mocha oa ho khanna ea bajari hangata e koaletsoe ho lera la khetla ha hs > λD ea khetla layer145. Считается, что в механизме восприятия этой структуры участвуют два фактора: (1) радиальная модуляция ДЭС оболочки и (2) эффект размытия электрического поля (рис. 8) 145. Исследователи отметили, что канал проводимости носителей в основном приурочено к оболочке, когда hs > λD оболочки145. Ho lumeloa hore lintlha tse peli li ameha ka mokhoa oa ho lemoha sebopeho sena: (1) radial modulation ea EDL ea khetla le (2) phello ea ho fifatsa sebaka sa motlakase (setšoantšo sa 8) 145. Bafuputsi ba hlokometse hore mocha o tsamaisang thepa o lula haholo-holo ho khetla ha hs > λD shells145.Ho lumeloa hore lintlha tse peli li tlatsetsa mochineng oa ho lemoha oa sebopeho sena: (1) ho feto-fetoha ha radial ea DEL ea khetla le (2) phello ea ho tlotsa masimo a motlakase (setšoantšo sa 8) 145.研究人员提到传导通道当壳层的hs > λD145 时，载流子的数量主要局限于壳层。 > λD145 时，载流子的数量主要局限于壳层. Исследователи отметили, что канал проводимости Когда hs > λD145 оболочки, количество носителей в основном ограничено оболочкой. Bafuputsi ba hlokometse hore mocha oa conduction Ha hs> λD145 ea khetla, palo ea bajari e fokotsoa haholo ke khetla.Ka hona, ka mokhoa o hanyetsanang oa mochine o thehiloeng ho CSHN, ho fetoha ha radial modulation ea cladding DEL ho hlōla (setšoantšo sa 8a).Leha ho le joalo, ho hs ≤ λD ea khetla, likaroloana tsa oksijene tse adsorbed ke khetla le heterojunction e entsoeng ho CS heterojunction e felile ka ho feletseng ka li-electrone. Ka hona, mocha oa conduction ha o fumanehe feela ka hare ho lera la khetla empa hape le karolo ea karolo ea mantlha, haholo-holo ha hs < λD ea lera la khetla. Ka hona, mocha oa conduction ha o fumanehe feela ka hare ho lera la khetla empa hape le karolo ea karolo ea mantlha, haholo-holo ha hs < λD ea lera la khetla. Поэтому канал проводимости располагается не только внутри оболочечного слоя, но и частично в сердцевинной части, особено придобение придцевной Ka hona, mocha oa conduction ha o fumanehe feela ka hare ho lera la khetla, empa hape le karolo ea karolo ea mantlha, haholo-holo ho hs < λD ea lera la khetla.因此，传导通道不仅位于壳层内部，而且部分位于芯部，尤其是当壳层的hs < λD 时. hs < λD 时. Поэтому канал проводимости располагается не только внутри оболочки, но и частично в сердцевине, особенно при hs < λD оболочки. Ka hona, mocha oa conduction ha o fumanehe feela ka har'a khetla, empa hape le karolo ea mantlha, haholo-holo ho hs < λD ea khetla.Tabeng ena, ka bobeli depleted elektrone khetla le karolo e itseng depleted konokono lera thusa modulate ho hanyetsa ea CSHN eohle, ho fellang ka phello ea motlakase tšimo mohatla (sa feiga. 8b).Lithuto tse ling li sebelisitse mohopolo oa karolo ea molumo oa EDL sebakeng sa mohatla oa tšimo ea motlakase ho sekaseka hs effect100,148.Ho nka menehelo ena e 'meli, ho feto-fetoha ha kakaretso ea khanyetso ea CSHN ho fihlela boleng ba eona bo boholo ha hs e bapisoa le sheath λD, joalokaha ho bontšitsoe setšoantšong sa 8c.Ka hona, hs e nepahetseng bakeng sa CSHN e ka ba haufi le khetla λD, e lumellanang le litlhaloso tsa liteko99,144,145,146,149.Liphuputso tse 'maloa li bontšitse hore hs e ka boela ea ama kutloisiso ea CSHN-based pn-heterojunction sensors40,148.Li et al.148 le Bai et al.40 e ile ea batlisisa ka mokhoa o hlophisehileng phello ea hs ts'ebetsong ea li-sensor tsa Pn-heterojunction CSHN, joalo ka TiO2@CuO le ZnO@NiO, ka ho fetola potoloho ea ALD ea cladding.Ka lebaka leo, boitšoaro ba maikutlo bo fetohile ho tloha ho mofuta oa p ho ea ho mofuta oa n ka ho eketseha ha hs40,148.Boitšoaro bona bo bakoa ke taba ea hore qalong (ka palo e lekanyelitsoeng ea lipotoloho tsa ALD) li-heterostructures li ka nkoa e le li-heteronanostructures tse fetotsoeng.Kahoo, mocha oa conduction o lekanyelitsoe ke lera la mantlha (p-type MOSFET), 'me sensor e bonts'a boitšoaro ba ho lemoha mofuta oa p.Ha palo ea lipotoloho tsa ALD e ntse e eketseha, lesela la cladding (n-type MOSFET) le fetoha quasi-continuous mme le sebetsa joalo ka mocha oa conduction, e leng se bakang kutloisiso ea mofuta oa n.Boitšoaro bo tšoanang ba phetoho ea maikutlo bo tlalehiloe bakeng sa pn branched heteronanostructures 150,151.Zhou et al.150 e ile ea batlisisa kutloisiso ea Zn2SnO4@Mn3O4 branched heteronanostructures ka ho laola litaba tsa Zn2SnO4 holim'a Mn3O4 nanowires.Ha li-nuclei tsa Zn2SnO4 li thehoa holim'a Mn3O4, ho ile ha bonoa maikutlo a mofuta oa p.Ka keketseho e 'ngoe ea litaba tsa Zn2SnO4, sensor e thehiloeng ho branched Zn2SnO4@Mn3O4 heteronanostructures e fetohela ho boits'oaro ba sensor ea mofuta oa n.
Tlhaloso ea mohopolo ea mochine oa sensor o sebetsang ka bobeli oa CS nanowires o bontšoa.a Resistance modulation ka lebaka la radial modulation ea likhetla tse felloang ke elektronike, b Phello e mpe ea ho tlotsa ka mokhoa oa ho hanyetsa, le c Kakaretso ea ho hanyetsa modulation ea CS nanowires ka lebaka la motsoako oa liphello tse peli 40
Qetellong, li-sensor tsa mofuta oa II li kenyelletsa li-nanostructures tse ngata tse fapaneng tsa hierarchical, 'me ts'ebetso ea sensor e itšetlehile haholo ka tlhophiso ea liteishene tsa conductive.Ka hona, ho bohlokoa ho laola boemo ba mocha oa conduction oa sensor le ho sebelisa mohlala o loketseng oa heteronanostructured MOS ho ithuta mokhoa o atolositsoeng oa kutlo oa li-sensors tsa mofuta oa II.
Mefuta ea sensor ea mofuta oa III ha e tloaelehe haholo, 'me mocha oa ho tsamaisa o thehiloe ho heterojunction e entsoeng pakeng tsa li-semiconductors tse peli tse amanang le li-electrode tse peli, ka ho latellana.Mehaho e ikhethang ea lisebelisoa hangata e fumanoa ka mekhoa ea micromachining mme mekhoa ea bona ea ho utloa e fapane haholo le meaho e 'meli e fetileng ea sensor.Lekhalo la IV la sensor ea Mofuta oa III hangata le bonts'a litšobotsi tse tloaelehileng tsa tokiso ka lebaka la sebopeho sa heterojunction48,152,153.Mokokotlo oa sebopeho sa I-V oa heterojunction e ntle e ka hlalosoa ka mochine oa thermionic oa emission ea elektronike holim'a bophahamo ba mokoallo oa heterojunction152,154,155.
moo Va ke leeme gagamalo, A ke sebaka sesebediswa, k ke Boltzmann kamehla, T ke mocheso feletseng, q ke mojari qoso, Jn le Jp ke lesoba le elektrone diffusion densities jwale, ka ho latellana.IS e emetse morao tjena saturation hajoale, e hlalosoang e le: 152,154,155
Ka hona, kakaretso ea hona joale ea pn heterojunction e itšetlehile ka phetoho ea khatello ea bajari ba litefiso le phetoho ea bophahamo ba mokoallo oa heterojunction, joalokaha ho bontšoa ho li-equations (3) le (4) 156
moo nn0 le pp0 e leng mahloriso a lielektrone (likoti) mofuteng oa n-(p-type) MOS, \(V_{bi}^0\) e leng bokhoni bo hahelletsoeng, Dp (Dn) ke coefficient ea phano ea li-electrons (likoti), Ln (Lp ) ke bolelele ba ho hasana ha lielektrone (likoti), ΔEv (ΔEc) ke phetoho ea matla ea sehlopha sa valence (leqhubu la conduction) ho heterojunction.Leha boima ba hona joale bo lekana le boima ba mopalami, bo ipapisitse le \(V_{bi}^0\).Ka hona, phetoho e akaretsang ea letsoalo la hona joale e itšetlehile haholo ka ho feto-fetoha ha bophahamo ba mokoallo oa heterojunction.
Joalokaha ho boletsoe ka holimo, ho thehoa ha li-MOSFET tsa hetero-nanostructured (mohlala, mofuta oa I le lisebelisoa tsa mofuta oa II) li ka ntlafatsa haholo ts'ebetso ea sensor, ho e-na le likarolo tsa motho ka mong.'Me bakeng sa lisebelisoa tsa mofuta oa III, karabo ea heteronanostructure e ka ba e phahameng ho feta likarolo tse peli48,153 kapa e phahameng ho feta karolo e le' ngoe76, ho itšetlehile ka lik'hemik'hale tsa thepa.Litlaleho tse 'maloa li bontšitse hore karabelo ea heteronanostructures e phahame haholo ho feta ea karolo e le' ngoe ha karolo e 'ngoe ea likarolo e sa tsotelle khase e reretsoeng48,75,76,153.Tabeng ena, khase e shebiloeng e tla sebelisana feela le lera le nang le kutloelo-bohloko 'me e etse hore ho be le phetoho ea Ef ea lera le tebileng le phetoho ea bophahamo ba mokoallo oa heterojunction.Joale kakaretso ea hona joale ea sesebelisoa e tla fetoha haholo, kaha e amana ka tsela e fapaneng le bophahamo ba mokoallo oa heterojunction ho ea ka equation.(3) le (4) 48,76,153.Leha ho le joalo, ha likarolo tsa mofuta oa n-type le p-type li le hlokolosi ho khase e shebiloeng, ts'ebetso ea ho lemoha e ka ba kae-kae lipakeng.José et al.76 e hlahisitse porous NiO / SnO2 filimi NO2 sensor ka ho sputtering 'me e fumane hore kutlo ea kutlo e ne e phahame feela ho feta ea NiO e thehiloeng ho sensor, empa e le tlase ho feta ea SnO2 e thehiloeng sensor.kutlo.Ketsahalo ena e bakoa ke taba ea hore SnO2 le NiO li bonts'a maikutlo a fapaneng le NO276.Hape, hobane likarolo tsena tse peli li na le maikutlo a sa tšoaneng a khase, li ka 'na tsa e-ba le tšekamelo e tšoanang ea ho lemoha oxidizing le ho fokotsa likhase.Ka mohlala, Kwon et al.157 e ile ea etsa tlhahiso ea NiO / SnO2 pn-heterojunction khase sensor ka oblique sputtering, joalokaha ho bontšitsoe setšoantšong sa 9a.Hoa thahasellisa hore mochine oa NiO / SnO2 pn-heterojunction o bontšitse mokhoa o tšoanang oa kutloisiso bakeng sa H2 le NO2 (setšoantšo sa 9a).Ho rarolla sephetho sena, Kwon et al.157 e ile ea batlisisa ka mokhoa o hlophisitsoeng kamoo NO2 le H2 li fetolang maikutlo a bajari le ho hlophisa \(V_{bi}^0\) ea lisebelisoa ka bobeli ho sebelisa mekhoa ea IV le lipapiso tsa k'homphieutha (Fig. 9bd).Lipalo tsa 9b le c li bonts'a bokhoni ba H2 le NO2 ho fetola boima ba li-sensor tse thehiloeng ho p-NiO (pp0) le n-SnO2 (nn0) ka ho latellana.Ba bontšitse hore pp0 ea mofuta oa p-NiO e fetohile hanyenyane tikolohong ea NO2, ha e ntse e fetoha haholo sebakeng sa H2 (setšoantšo sa 9b).Leha ho le joalo, bakeng sa n-mofuta oa SnO2, nn0 e itšoara ka tsela e fapaneng (Setšoantšo sa 9c).Ho itšetlehile ka liphello tsena, bangoli ba ile ba etsa qeto ea hore ha H2 e sebelisoa ho sensor e thehiloeng ho NiO / SnO2 pn heterojunction, keketseho ea nn0 e lebisitse ho eketseha ha Jn, 'me \(V_{bi}^0\) e lebisitse ho ho fokotseha ha karabo (setšoantšo sa 9d).Ka mor'a ho pepesehela NO2, ka bobeli ho fokotseha ho hoholo ha nn0 ho SnO2 le keketseho e nyenyane ea pp0 ho NiO ho lebisa ho fokotseha ho hoholo ho \ (V_{bi} ^ 0 \), e leng se tiisang keketseho ea karabo ea kutlo (setšoan 9d). ) 157 Qetellong, liphetoho ka har'a mahloriso a bajari le \(V_{bi}^0\) li lebisa ho liphetoho ho kakaretso ea hona joale, e leng ho tsoelang pele ho ama bokhoni ba ho lemoha.
Mokhoa oa ho utloa oa sensor ea khase o thehiloe holim'a sebopeho sa sesebelisoa sa Mofuta oa III.Ho hlahloba electron microscopy (SEM) litšoantšo tse fapaneng, p-NiO/n-SnO2 sesebelisoa sa nanocoil le thepa ea sensor ea p-NiO/n-SnO2 nanocoil heterojunction sensor ho 200 ° C bakeng sa H2 le NO2;b , SEM ea likarolo tse ling tsa c-sesebelisoa, le liphetho tsa ketsiso ea sesebelisoa se nang le p-NiO b-layer le n-SnO2 c-layer.Sensor ea b p-NiO le c n-SnO2 sensor e lekanya le ho bapisa litšobotsi tsa I-V moeeng o omileng le ka mor'a ho pepesehela H2 le NO2.'Mapa oa mahlakore a mabeli a sekhahla sa b-hole ho p-NiO le' mapa oa li-c-electrone lera la n-SnO2 le sekala sa mebala li ile tsa etsoa mohlala ho sebelisoa software ea Sentaurus TCAD.d Liphetho tsa ho etsisa tse bontšang 'mapa oa 3D oa p-NiO/n-SnO2 moeeng o omileng, H2 le NO2157 tikolohong.
Ntle le lisebelisoa tsa lik'hemik'hale tsa thepa ka boeona, sebopeho sa sesebelisoa sa Mofuta oa III se bontša monyetla oa ho iketsetsa lisebelisoa tsa khase tse ikemetseng, tse ke keng tsa khoneha ka lisebelisoa tsa Mofuta oa I le oa Mofuta oa II.Ka lebaka la tšimo ea bona ea tlhaho ea motlakase (BEF), mehaho ea diode ea pn heterojunction e atisa ho sebelisoa ho haha lisebelisoa tsa photovoltaic le ho bontša bokhoni ba ho iketsetsa lisebelisoa tsa khase ea photoelectric ka mocheso oa kamore tlas'a illumination74,158,159,160,161.BEF ho heterointerface, e bakoang ke phapang ea maemo a Fermi ea thepa, e boetse e tlatsetsa karohanong ea lipara tsa electron-hole.Molemo oa mochine oa khase oa photovoltaic o nang le matla a matla ke matla a fokolang a matla kaha a ka khona ho nka matla a leseli le khanyang ebe o laola ka boeona kapa lisebelisoa tse ling tse nyenyane ntle le tlhokahalo ea mohloli oa matla a ka ntle.Ka mohlala, Tanuma le Sugiyama162 li entse NiO / ZnO pn heterojunctions e le lisele tsa letsatsi ho kenya lisebelisoa tsa SnO2-based polycrystalline CO2.Gad le ba bang.74 e tlalehile mochine o ikemetseng oa khase ea photovoltaic e thehiloeng ho Si / ZnO @ CdS pn heterojunction, joalokaha ho bontšitsoe setšoantšong sa 10a.Li-nanowires tsa ZnO tse shebileng holimo li ne li holisitsoe ka kotloloho holim'a likaroloana tsa silicon tsa mofuta oa p ho theha Si/ZnO pn heterojunctions.Joale li-nanoparticles tsa CdS li ile tsa fetoloa holim'a ZnO nanowires ka phetoho ea lik'hemik'hale.Ka feiga.10a e bonts'a liphetho tsa karabelo ea sensor ea Si/ZnO@CdS e sa sebetseng bakeng sa O2 le ethanol.Tlas'a khanya, motlakase o bulehileng oa potoloho (Voc) ka lebaka la ho arohana ha li-electron-hole pairs nakong ea BEP ho Si / ZnO heterointerface e eketseha ka mokhoa o lekanang le palo ea diode tse amanang74,161.Voc e ka emeloa ke equation.(5) 156,
moo ND, NA, le Ni e leng likhakanyo tsa bafani, ba amohelang, le bajari ba ka hare, ka ho latellana, 'me k, T, le q e le liparamente tse tšoanang le tsa equation e fetileng.Ha ba pepesehetse likhase tsa oxidizing, ba ntša li-electrone ho tloha ho ZnO nanowires, e leng se lebisang ho fokotseha ha \(N_D^{ZnO}\) le Voc.Ka lehlakoreng le leng, ho fokotseha ha khase ho ile ha fella ka keketseho ea Voc (setšoantšo sa 10a).Ha u khabisa ZnO ka li-nanoparticles tsa CdS, li-electrone tse nang le photoexcited ka CdS nanoparticles li kenngoa ka har'a sehlopha sa conduction sa ZnO 'me li sebelisana le khase ea adsorbed, kahoo li eketsa bokhoni ba pono74,160.Sensor e tšoanang ea khase ea photovoltaic e thehiloeng ho Si / ZnO e tlalehiloe ke Hoffmann et al.160, 161 (setšoantšo sa 10b).Sensor ena e ka lokisoa ho sebelisoa mohala oa amine-functionalized ZnO nanoparticles ([3-(2-aminoethylamino) propyl] trimethoxysilane) (amino-functionalized-SAM) le thiol ((3-mercaptopropyl) -functionalized, ho fetola mosebetsi oa mosebetsi. ea khase e lebisitsoeng bakeng sa ho khetholla ho khetholla ha NO2 (trimethoxysilane) (thiol-functionalized-SAM)) (Setšoantšo sa 10b) 74,161.
Sensor ea khase ea khase ea photoelectric e ikemetseng e itšetlehileng ka sebopeho sa sesebelisoa sa mofuta oa III.mochine o ikemetseng oa khase ea photovoltaic e thehiloeng ho Si / ZnO @ CdS, mochine oa ho iponahatsa o ikemetseng le karabo ea sensor ho oxidized (O2) le ho fokotsa (1000 ppm ethanol) likhase tlas'a letsatsi;74b Self-powered photovoltaic gas sensor e thehiloeng ho li-sensor tsa Si ZnO/ZnO le likarabo tsa sensor ho likhase tse fapaneng ka mor'a ts'ebetso ea ZnO SAM e nang le li-terminal amines le thiols 161
Ka hona, ha ho buuoa ka mochine o nang le kutloelo-bohloko oa li-sensor tsa mofuta oa III, ke habohlokoa ho tseba phetoho bophahamong ba mokoallo oa heterojunction le bokhoni ba khase ho susumetsa mahloriso a mokhanni.Ho feta moo, khanya e ka hlahisa lik'hasete tse hlahisoang ke lifoto tse sebetsanang le likhase, e leng se tšepisang ho lemoha khase e itšebetsang.
Joalokaha ho boletsoe tlhahlobong ena ea lingoliloeng, mefuta e mengata e fapaneng ea MOS heteronanostructures e entsoe ho ntlafatsa ts'ebetso ea sensor.Setsi sa Marang-rang sa Saense se ile sa batlisisoa bakeng sa mantsoe a fapaneng a bohlokoa (metal oxide composite, core-sheath metal oxides, layered metal oxides, le li-self-powered analyzers) hammoho le litšoaneleho tse ikhethang (bongata, kutloisiso / khetho, bokhoni ba ho hlahisa matla, tlhahiso) .Mokhoa Litšobotsi tsa lisebelisoa tse tharo ho tse tharo li bonts'itsoe ho Lethathamo la 2. Khopolo ea kakaretso ea moralo bakeng sa lisebelisoa tse phahameng tsa khase e tšohloa ka ho hlahloba lintlha tse tharo tsa bohlokoa tse hlahisitsoeng ke Yamazoe.Mechanisms for MOS Heterostructure Sensors Ho utloisisa lintlha tse susumetsang li-sensors tsa khase, li-parameter tse fapaneng tsa MOS (mohlala, boholo ba lijo-thollo, mocheso oa ts'ebetso, sekoli le sekhahla sa sekheo sa oksijene, lifofane tse bulehileng tsa kristale) li ithutile ka hloko.Sebopeho sa sesebelisoa, seo hape se leng bohlokoa ho boits'oaro ba sensor, se hlokomolohuoe ebile ha se hangata ho buisanoang ka sona.Tlhahlobo ena e tšohla mekhoa ea motheo ea ho lemoha mefuta e meraro e tloaelehileng ea sebopeho sa lisebelisoa.
Sebopeho sa boholo ba lijo-thollo, mokhoa oa tlhahiso, le palo ea li-heterojunctions tsa lisebelisoa tsa kutlo ho mofuta oa mofuta oa I li ka ama haholo kutloisiso ea kutlo.Ho phaella moo, boitšoaro ba sensor bo boetse bo angoa ke tekanyo ea molar ea likaroloana.Mefuta ea lisebelisoa tsa mofuta oa II (li-decorative heteronanostructures, bilayer kapa lifilimi tsa multilayer, HSSNs) ke lisebelisoa tse ratoang ka ho fetisisa tse nang le likarolo tse peli kapa ho feta, 'me karolo e le' ngoe feela e kopantsoe le electrode.Bakeng sa sebopeho sena sa sesebelisoa, ho khetholla sebaka sa liteishene tsa conduction le liphetoho tse amanang le tsona ke tsa bohlokoa ho ithuteng mokhoa oa ho lemoha.Hobane lisebelisoa tsa mofuta oa II li kenyelletsa li-heteronanostructures tse ngata tse fapaneng, ho hlahisitsoe mekhoa e mengata e fapaneng ea ho utloa.Ka sebopeho sa mofuta oa III oa kutlo, mocha oa ho khanna o laoloa ke heterojunction e entsoeng ka heterojunction, 'me mokhoa oa ho lemoha o fapane ka ho feletseng.Ka hona, ke habohlokoa ho fumana phetoho bophahamong ba mokoallo oa heterojunction ka mor'a ho pepeseha ha khase e lebisitsoeng ho mofuta oa mofuta oa III.Ka moqapi ona, li-sensor tsa khase ea photovoltaic tse ikemetseng li ka etsoa ho fokotsa tšebeliso ea matla.Leha ho le joalo, kaha ts'ebetso ea hajoale ea ho etsa maqheka e batla e rarahane, 'me kutloelo-bohloko e tlase haholo ho feta li-sensors tsa khase tsa chemo-resistive gas tse tloaelehileng, ho ntse ho e-na le tsoelo-pele e ngata lipatlisisong tsa li-sensors tsa khase tse itšebetsang.
Melemo ea mantlha ea li-sensor tsa MOS tsa khase tse nang le li-hierarchical heteronanostructures ke lebelo le kutlo e phahameng.Leha ho le joalo, mathata a mang a bohlokoa a li-sensor tsa khase ea MOS (mohlala, mocheso o phahameng oa ts'ebetso, botsitso ba nako e telele, khetho e fosahetseng le ho ikatisa, liphello tsa mongobo, joalo-joalo) li ntse li le teng 'me li hloka ho rarolloa pele li ka sebelisoa lits'ebetsong tse sebetsang.Li-sensor tsa mehleng ea kajeno tsa MOS hangata li sebetsa ka mocheso o phahameng 'me li sebelisa matla a mangata, a amang botsitso ba nako e telele ea sensor.Ho na le mekhoa e 'meli e tloaelehileng ea ho rarolla bothata bona: (1) nts'etsopele ea lisebelisoa tse tlaase tsa matla a tlaase;(2) nts'etsopele ea lisebelisoa tse ncha tse bonolo tse ka sebetsang ka mocheso o tlase kapa esita le mocheso oa kamore.Mokhoa o mong oa nts'etsopele ea li-sensor tse nang le matla a tlase ke ho fokotsa boholo ba sensor ka ho etsa lipoleiti tse futhumatsang mocheso tse thehiloeng ho li-ceramics le silicon163.Lipoleiti tse futhumatsang tse thehiloeng ka ceramic li sebelisa hoo e ka bang 50-70 mV ka sensor, ha lipoleiti tse futhumatsang tsa silicon tse ntlafalitsoeng li ka ja hanyane joalo ka 2 mW ka sensor ha e sebetsa e sa khaotse ho 300 ° C163,164.Nts'etsopele ea lisebelisoa tse ncha tsa kutlo ke mokhoa o sebetsang oa ho fokotsa tšebeliso ea matla ka ho theola mocheso o sebetsang, hape o ka ntlafatsa botsitso ba sensor.Ha boholo ba MOS bo ntse bo tsoela pele ho fokotseha ho eketsa kutloisiso ea kutlo, botsitso ba mocheso oa MOS bo fetoha phephetso e kholo, e leng se ka lebisang ho hoholeha ka pontšo ea sensor165.Ho phaella moo, mocheso o phahameng o khothalletsa ho ata ha thepa ho heterointerface le ho thehoa ha mekhahlelo e tsoakiloeng, e amang thepa ea elektronike ea kutlo.Bafuputsi ba tlaleha hore mocheso o nepahetseng oa ho sebetsa oa sensor o ka fokotsoa ka ho khetha lisebelisoa tse loketseng tsa ho utloa le ho nts'etsapele MOS heteronanostructures.Ho batla mokhoa o tlaase oa mocheso oa ho etsa li-heteronanostructures tsa MOS tse khanyang haholo ke mokhoa o mong o tšepisang oa ho ntlafatsa botsitso.
Khetho ea li-sensor tsa MOS ke taba e 'ngoe e sebetsang kaha likhase tse fapaneng li lula hammoho le khase e shebiloeng, ha li-sensor tsa MOS hangata li na le khase e fetang e le' ngoe 'me hangata li bonts'a kutloelo-bohloko.Ka hona, ho eketsa khetho ea sensor ho khase e shebiloeng hammoho le likhase tse ling ho bohlokoa bakeng sa lits'ebetso tse sebetsang.Lilemong tse mashome a seng makae tse fetileng, khetho e 'nile ea rarolloa ka ho haha li-sensor tsa khase tse bitsoang "linko tsa elektroniki (E-nose)" hammoho le li-algorithms tsa tlhahlobo ea computational joalo ka koetliso ea vector quantization (LVQ), principal component analysis (PCA), joalo-joalo e.Mathata a thobalano.Partial Least Squares (PLS), joalo-joalo 31, 32, 33, 34. Lintlha tse peli tse ka sehloohong (palo ea li-sensor, tse amanang haufi-ufi le mofuta oa lisebelisoa tsa kutlo, le tlhahlobo ea computational) li bohlokoa ho ntlafatsa bokhoni ba linko tsa elektroniki. ho khetholla likhase169.Leha ho le joalo, ho eketsa palo ea li-sensor hangata ho hloka mekhoa e mengata e rarahaneng ea tlhahiso, kahoo ho bohlokoa ho fumana mokhoa o bonolo oa ho ntlafatsa ts'ebetso ea linko tsa elektroniki.Ntle le moo, ho fetola MOS ka lisebelisoa tse ling ho ka eketsa khetho ea sensor.Ka mohlala, khetho e khethiloeng ea H2 e ka finyelloa ka lebaka la ts'ebetso e ntle ea catalytic ea MOS e fetotsoeng ka NP Pd.Lilemong tsa morao tjena, bafuputsi ba bang ba koahetse sebaka sa MOS MOF ho ntlafatsa khetho ea sensor ka ho kenyelletsa boholo171,172.E bululetsoe ke mosebetsi ona, ts'ebetso ea lisebelisoa e ka rarolla bothata ba ho khetha.Leha ho le joalo, ho sa ntsane ho e-na le mosebetsi o mongata o lokelang ho etsoa ho khetha thepa e nepahetseng.
Ho pheta-pheta ha litšobotsi tsa li-sensor tse entsoeng tlas'a maemo le mekhoa e tšoanang ke tlhokahalo e 'ngoe ea bohlokoa bakeng sa tlhahiso e kholo le lisebelisoa tse sebetsang.Ka tloaelo, mekhoa ea centrifugation le ea ho qoelisoa ke mekhoa e theko e tlaase ea ho etsa li-sensor tsa khase e phahameng.Leha ho le joalo, nakong ea lits'ebetso tsena, lisebelisoa tse nang le kutloelo-bohloko li atisa ho bokellana 'me kamano pakeng tsa lisebelisoa tse hlokolosi le substrate e fetoha e fokolang68, 138, 168. Ka lebaka leo, kutloisiso le botsitso ba sensor li senyeha haholo, 'me ts'ebetso e fetoha hape.Mekhoa e meng ea ho etsa lintho tse kang sputtering, ALD, pulsed laser deposition (PLD), le physical vapor deposition (PVD) e lumella tlhahiso ea lifilimi tsa MOS tsa bilayer kapa tsa multilayer ka ho toba holim'a silicon e entsoeng ka mohlala kapa alumina substrates.Mekhoa ena e qoba ho bokellana ha lisebelisoa tse bonolo, e netefatsa ho ikatisa ha sensor, le ho bonts'a monyetla oa tlhahiso e kholo ea li-sensor tsa filimi tse tšesaane tse planar.Leha ho le joalo, kutloisiso ea lifilimi tsena tse bataletseng ka kakaretso e tlase haholo ho feta ea lisebelisoa tsa 3D nanostructured ka lebaka la sebaka sa tsona se senyenyane se khethehileng le ho fokotseha ha khase41,174.Maano a macha a ho holisa li-heteronanostructures tsa MOS libakeng tse ikhethileng ho li-microarrays tse hlophisitsoeng le ho laola ka nepo boholo, botenya, le morphology ea lisebelisoa tse bobebe li bohlokoa bakeng sa ho etsoa ka theko e tlase ea li-sensor tsa boemo ba wafer tse nang le ho ikatisa ho hoholo le kutlo.Ka mohlala, Liu et al.174 e hlahisitse leano le kopaneng la holimo-tlase le tlase-holimo bakeng sa ho etsa likristale tsa boleng bo holimo ka ho hola maboteng a situ Ni(OH)2 nanowall libakeng tse itseng..Li-wafers bakeng sa li-microburners.
Ntle le moo, ho bohlokoa hape ho nahana ka phello ea mongobo ho sensor lits'ebetsong tse sebetsang.Limolek'hule tsa metsi li ka qothisana lehlokoa le limolek'hule tsa oksijene bakeng sa libaka tsa adsorption ho lisebelisoa tsa sensor mme li ama boikarabello ba sensor bakeng sa khase e shebiloeng.Joalo ka oksijene, metsi a sebetsa joalo ka molek'hule ka sorption ea 'mele, hape a ka ba teng ka sebopeho sa hydroxyl radicals kapa lihlopha tsa hydroxyl liteisheneng tse fapaneng tsa oxidation ka chemisorption.Ho phaella moo, ka lebaka la boemo bo phahameng le mongobo o fapaneng oa tikoloho, karabo e ka tšeptjoang ea sensor ho khase e lebisitsoeng ke bothata bo boholo.Ho 'nile ha etsoa mekhoa e mengata ea ho rarolla bothata bona, joalo ka khase ea preconcentration177, matšeliso a mongobo le mekhoa ea li-cross-reactive lattice178, hammoho le mekhoa ea ho omisa179,180.Leha ho le joalo, mekhoa ena e theko e boima, e rarahaneng, 'me e fokotsa kutlo ea kutlo.Ho 'nile ha etsoa tlhahiso ea maqheka a 'maloa a theko e tlaase ho thibela liphello tsa mongobo.Ka mohlala, ho khabisa SnO2 ka Pd nanoparticles ho ka khothalletsa phetoho ea oksijene ea adsorbed hore e be likaroloana tsa anionic, ha e ntse e sebetsa SnO2 ka thepa e nang le kamano e phahameng ea limolek'hule tsa metsi, tse kang NiO le CuO, ke litsela tse peli tsa ho thibela ho itšetleha ha mongobo ka limolek'hule tsa metsi..Li-sensor 181, 182, 183. Ho phaella moo, phello ea mongobo e ka boela ea fokotsoa ka ho sebelisa lisebelisoa tsa hydrophobic ho theha libaka tsa hydrophobic36,138,184,185.Leha ho le joalo, nts'etsopele ea li-sensor tsa khase e hananang le mongobo e ntse e le qalong, 'me ho hlokahala maano a tsoetseng pele ho rarolla mathata ana.
Qetellong, ntlafatso ea ts'ebetso ea ho lemoha (mohlala, kutloisiso, khetho, mocheso o tlaase o sebetsang hantle) li fihletsoe ka ho theha MOS heteronanostructures, 'me mekhoa e mengata e ntlafalitsoeng ea ho lemoha e hlahisitsoe.Ha u ithuta mokhoa oa ho utloa oa sensor e itseng, sebopeho sa geometri sa sesebelisoa se tlameha ho nkoa hape.Ho tla hlokahala lipatlisiso mabapi le lisebelisoa tse ncha tsa ho lemoha le ho etsa lipatlisiso mabapi le maano a tsoetseng pele a ho etsa maqheka ho ntlafatsa ts'ebetso ea li-sensor tsa khase le ho rarolla mathata a setseng nakong e tlang.Bakeng sa tokiso e laoloang ea litšobotsi tsa sensor, hoa hlokahala ho theha kamano lipakeng tsa mokhoa oa maiketsetso oa lisebelisoa tsa sensor le ts'ebetso ea heteronanostructures.Ntle le moo, boithuto ba karabelo ea bokaholimo le liphetoho ho li-heterointerfaces tse sebelisang mekhoa ea sejoale-joale ea sebopeho se ka thusa ho hlakisa mekhoa ea maikutlo a bona le ho fana ka likhothaletso bakeng sa nts'etsopele ea li-sensor tse ipapisitseng le thepa ea heteronanostructured.Qetellong, boithuto ba maano a sejoale-joale a ho etsa li-sensor bo ka lumella ho etsoa ha li-sensor tsa khase tse nyane maemong a li-wafer bakeng sa lits'ebetso tsa bona tsa indasteri.
Genzel, NN et al.Thuto ea longitudinal ea maemo a ka hare a nitrogen dioxide le matšoao a ho hema ho bana ba nang le asthma libakeng tsa litoropo.Tikoloho.Pono ea bophelo bo botle.116, 1428–1432 (2008).
Nako ea poso: Nov-04-2022
