Seo u se tsebang ka li-sensor tsa electrochemical

Sensor ea electrochemical ke mofuta oa kutlo o itšetlehileng ka thepa ea electrochemical ea analyte ho fetisetsa bongata ba lik'hemik'hale ka bongata ba motlakase bakeng sa ho utloa le ho lemoha.

Li-sensor tsa khale tsa electrochemical li qalile lilemong tsa bo-1950, ha li ne li sebelisetsoa ho lekola oksijene. 'Me ho fihlela lilemong tsa bo-1980, ha li ne li sebelisoa ho beha leihlo mefuta e mengata ea likhase tse chefo' me li bontša kutlo e ntle le ho khetha.

Ⅰ. Molao-motheo o sebetsang oa sensor ea electrochemical

 Lisensara tsa electrochemical li sebetsa ka ho sebetsa ka lik'hemik'hale ha khase e ntse e lekanngoa le ho hlahisa lets'oao la motlakase le ipapisitseng le khatello ea khase. Boholo ba li-sensor tsa khase ea electrochemical li hlahisa hona joale ka mokhoa o lekanang le khatello ea khase.

 Sensor ea khase ea electrochemical e sebetsa ka tsela e latelang: Limolek'hule tsa khase tse shebiloeng tse kopanang le sensor li qala ho feta ka har'a diaphragm e thibelang ho kolobisoa hape e sebetsa joalo ka mokoallo oa lerōle. Joale limolek'hule tsa khase li hasana ka har'a tube ea capillary, mohlomong ka sefe e latelang, ebe ka lesela la hydrophobic ho ea ka holim'a electrode ea kutlo. Ha li le moo, limolek'hule li na le oxidised kapa li fokotsehile, ka hona li hlahisa kapa li ja lielektrone ho etsa hore motlakase o be teng.

 Ke habohlokoa ho hlokomela hore palo ea limolek'hule tsa khase tse kenang ho sensor ka tsela ena li lekanyelitsoe ke ho hasana ka capillary. Ka ho ntlafatsa tsela, lets'oao le nepahetseng la motlakase le fumanoa ho latela mefuta e lakatsehang ea litekanyo. Moralo oa li-electrode tse utloang o bohlokoa ho fihlela karabelo e phahameng ho khase e shebiloeng le ho hatella likarabo tse sa batleheng ho likhase tse sitisang. E kenyelletsa tsamaiso ea mekhahlelo e meraro bakeng sa lintho tse tiileng, metsi le likhase, 'me kaofela li kenyelletsa ho tsebahatsa lik'hemik'hale tsa khase ea analyte. Sele ea electrochemical e phethoa ke seo ho thoeng ke counter electrode, Cont electrode, e lekanyang karabelo ho electrode ea kutlo. Hona joale ionic pakeng tsa Cont electrode le Sen electrode e tsamaisoa ke electrolyte ka har'a 'mele oa kutlo, ha tsela ea hona joale e fanoa ka mohala o felisitsoeng ke sehokelo sa pin. Hangata electrode ea boraro e kenyelelitsoe ho li-sensor tsa electrochemical (3-electrode sensors). Seo ho thoeng ke "referense electrode" se sebelisetsoa ho boloka bokhoni ba electrode ea kutlo ka boleng bo tsitsitseng. Bakeng sa morero ona mme hangata bakeng sa ts'ebetso ea li-electrochemical sensors, ho hlokahala hore ho be le potoloho e sa feleng.

Ⅱ. Likarolo tsa sensor ea electrochemical

Sensor ea electrochemical e na le likarolo tse 'nè tsa bohlokoa tse latelang:

1. Li-membrane tse phefumolohang (tse tsejoang hape e le li-membrane tsa hydrophobic): Li-membrane tsena li sebetsa ho koahela li-electrode tse utloang (catalytic) 'me, maemong a mang, li laola boima ba limolek'hule tsa likhase tse fihlang holim'a electrode. Ka tloaelo, li-membrane tsena li entsoe ka lifilimi tsa Teflon tse nang le porosity e tlaase. Ha li-membrane tsena li sebelisoa ho koahela li-electrode, li-sensor li bitsoa li-sensor tse koahetsoeng. Ntle le moo, filimi ea Teflon ea porosity e phahameng e ka sebelisoa, hammoho le capillary, ho laola boima ba molek'hule ea khase e fihlang holim'a electrode. Sebopeho sena se tsejoa e le sensor ea mofuta oa capillary. Ntle le ho fana ka tšireletso ea mochine bakeng sa kutlo, filimi e boetse e sebetsa e le filthara, e tlosa likaroloana tse sa batleheng. Ho etsa bonnete ba hore boima bo nepahetseng ba molek'hule ba khase bo lumelloa ho feta, ho bohlokoa ho khetha boholo bo loketseng ba lesoba bakeng sa lera le capillary. The aperture size e tlameha ho lumella limolek'hule tse lekaneng tsa khase hore li fihle ho electrode ea kutlo ha li ntse li thibela ho lutla kapa ho omisa ka potlako ha electrolyte ea mokelikeli.

2. Electrode: Ho bohlokoa ho khetha ka hloko lisebelisoa tsa elektrode. Thepa e lokela ho ba ea matla, e khonang ho etsa semi-electrolytic reaction ka nako e telele. Ka tloaelo, li-electrode li entsoe ka litšepe tsa bohlokoa, joalo ka platinum kapa khauta, tse sebetsanang hantle le limolek'hule tsa khase ka catalysis. Ho ipapisitse le moralo oa sensor, li-electrode tse tharo li ka hahuoa ho tsoa lisebelisoa tse fapaneng ho thusa karabelo ea electrolysis.

3. Electrolyte: Electrolyte e tlameha ho khona ho nolofatsa mekhoa ea electrolytic le ho fetisetsa ka katleho tefiso ea ionic ho electrode. E tlameha hape ho theha bokhoni bo tsitsitseng ba litšupiso le electrode ea referense mme e lumellane le lisebelisoa tse sebelisoang ka har'a sensor. Ho feta moo, mouoane o potlakileng oa electrolyte o ka lebisa ho fokotseha ha lets'oao la sensor, ho ka senyang ho nepahala le ho tšepahala ha lona.

4. Lisebelisoa: Ka linako tse ling, li-filters tsa scrubber li behoa ka pel'a sensor ho felisa likhase tse sa batleheng. Khetho ea li-filters e na le moeli, 'me mofuta o mong le o mong o bonts'a boemo bo ikhethang ba ho sebetsa hantle. Khabone e kentsoeng e eme e le sesebelisoa se sefang se sebelisoang haholo ho fetisisa, se sefang lik'hemik'hale tse ngata, ho sa kenyeletsoe carbon monoxide. Ka ho khetha ka hloko mecha ea litaba ea filthara, li-sensor tsa electrochemical li fihlela khetho e phahameng ho ea ho likhase tse reriloeng.

Ⅲ. Sehlopha sa Sensor ea Electrochemical

Ho na le mekhoa e mengata ea ho khetholla li-sensor tsa electrochemical. Ho ipapisitsoe le mats'oao a bona a fapaneng a tlhahiso, a ka aroloa ka li-sensor tsa potentiometric, li-amperometric sensors le li-conductometric sensors.

Ho latela lintho tse bonoang ke li-sensor tsa electrochemical, li-sensor tsa electrochemical li ka aroloa haholo-holo ho li-ion sensors, li-sensors tsa khase le li-biosensors.

Ⅳ. Thepa e ka Sehloohong le Lintlha tse Susumetsang

1. Bonolo

Lintlha tse ka sehloohong tse amang kutloisiso li kenyelletsa: ts'ebetso ea catalyst, ho kenngoa ha moea, electrolyte conductivity, le mocheso o potolohileng.

2. Ho hlaphoheloa karabelo

Lintlha tse ka sehloohong tse amang lebelo la ho hlaphoheloa ha karabelo ke ts'ebetso ea catalyst, conductivity ea electrolyte, mohaho oa kamore ea khase, thepa ea khase, joalo-joalo.

3. Ho khetha / ho kena-kenana le ho feta

Lintlha tse ka sehloohong tse amang khetho li kenyelletsa mofuta oa catalyst, electrolyte, bias voltage, filter, joalo-joalo.

4. Pheta-pheta/Botsitso ba nako e telele

Lintho tse amang ho pheta-pheta li kenyelletsa: botsitso ba sebopeho sa electrode, botsitso ba electrolyte, botsitso ba potoloho ea khase, joalo-joalo.

5, Ts'ebetso e phahameng le e tlase ea mocheso

Lintho tse amang botsitso ba mocheso o phahameng le o tlase li kenyelletsa: ts'ebetso ea catalyst, botsitso ba sebopeho sa electrode, le litšobotsi tsa khase.

V. Lisebelisoa tse 'nè tse kholo tsa lisebelisoa tsa electrochemical

Li-sensor tsa electrochemical li sebelisoa haholo libakeng tsa indasteri le tsa sechaba tsa ho lemoha khase, li khona ho bona ozone, formaldehyde, carbon monoxide, ammonia, hydrogen sulfide, sulfur dioxide, nitrogen dioxide, oksijene le likhase tse ling, tse sebelisoang hangata ho lisebelisoa tse nkehang habonolo le lisebelisoa tsa tlhahlobo ea khase inthaneteng.

1. Sensor ea mongobo

Mongobo ke pontšo ea bohlokoa ea tikoloho ea moea, mongobo oa moea le 'mele oa motho o na le kamano e haufi pakeng tsa mocheso oa mouoane, mocheso o phahameng le mongobo o phahameng, ka lebaka la mathata a' mele oa motho oa ho fetoha mouoane oa metsi le ho ikutloa o le mouoane, mocheso o tlaase le mongobo o phahameng, mokhoa oa ho senya mocheso oa 'mele oa motho o matla, o bonolo ho baka serame le serame. Mocheso o loketseng haholo bakeng sa 'mele oa motho ke 18 ~ 22 ℃, mongobo o lekanyelitsoeng ke 35% ~ 65% RH. Tikolohong le tlhokomelong ea bophelo bo botle, hangata e sebelisoa ho thermo-hygrometer e metsi, hygrometer ea letsoho le hygrometer ea moea le lisebelisoa tse ling ho fumana mongobo oa moea.

Lilemong tsa morao tjena, palo e kholo ea lingoliloeng e tlaleha ka tšebeliso ea li-sensor ho fumana mongobo oa moea. Likristale tse koahetsoeng ka piezoelectric quartz tse sebelisetsoang ho etsa qeto ea mongobo o lekanyelitsoeng li entsoe ka likristale tse nyane tsa quartz piezoelectric ka mokhoa oa photolithography le mekhoa ea ho kopanya lik'hemik'hale, 'me lintho tse' nè li koahetsoe ka likristale tsa quartz tsa AT-cut 10 MHz, tse nang le kutlo e phahameng ea mongobo ho mongobo. kristale ke resonator potolohong ea oscillating eo maqhubu a eona a fapaneng le boima, 'me ka ho khetha seaparo se loketseng, sensor e ka sebelisoa ho fumana hore na mongobo o lekanyelitsoeng oa likhase tse fapaneng. Boikutlo, mokhoa oa ho arabela, nako ea ho arabela, khetho, hysteresis le bophelo bohle ba sensor e itšetlehile ka mofuta oa lik'hemik'hale tsa ho roala.

2, sensor ea naetrojene

Nitrogen oxide ke mefuta e fapaneng ea oxides ea naetrojene e entsoeng ka motsoako oa likhase, hangata e hlalosoang e le NOX. Ka oxide ea naetrojene, mefuta e fapaneng ea botsitso ba lik'hemik'hale tsa nitrogen oxide e fapane, moea o atisa ho aroloa ka likarolo tse batlang li tsitsitse tsa lik'hemik'hale tsa nitrogen monoxide le nitrogen dioxide, bohlokoa ba bona bohloeki bo bonahala bo le bohlokoa ho feta mefuta e meng ea nitrogen oxide.

Ha ho hlahlojoa tikoloho, nitrogen oxide ka kakaretso e bolela nitrogen dioxide. Mokhoa o tloaelehileng oa China oa ho lekola nitrogen oxides ke mokhoa oa colourimetric oa naphthalene ethylenediamine hydrochloride, kutlo ea mokhoa ke 0.25ug/5ml, mokhoa oa ho fetola coefficient o angoa ke sebopeho sa tharollo e monyang, khatello ea nitrogen dioxide, lebelo. ea pokello ea khase, sebopeho sa tube e monyang, ho phela hammoho ha li-ion le mocheso le lintlha tse ling tse ngata, tse sa kopane ka ho feletseng. Boikemisetso ba kutlo ke mokhoa o mocha o ntlafalitsoeng lilemong tsa morao tjena.

3, Sensor ea Khase ea Hydrogen Sulfide

Hydrogen sulfide ke khase e se nang 'mala, e tukang, e nang le monko o khethehileng oa lehe le bolileng, le halefisang le ho hema, le kotsi 'meleng oa motho. Mekhoa e mengata e sebelisa calorimetry le chromatography ea khase ho fumana hore na hydrogen sulfide e teng moeeng. Boikemisetso ba litšila tsa moea tseo litaba tsa tsona hangata li leng tlase joalo ka boemo ba mg/m3 ke e 'ngoe ea lits'ebetso tsa mantlha tsa li-sensors tsa khase, empa li-sensor tsa khase ea semiconductor ha li khone ho fihlela litlhoko tsa kutlo le khetho ea ho beha leihlo likhase tse itseng tse silafatsang ka nako e khuts'oane. tsa nako.

Sehlopha sa sensor ea filimi e tšesaane e entsoeng ka silevera e na le li-sensor tse 'ne tse rekotang ka nako e le' ngoe likhahla tsa sulfur dioxide le hydrogen sulfide li sebelisa analyzer ea bokahohle e thehiloeng ho coulometric titration le matšoao a tsoang ho semiconductor gas sensor array. Boikoetliso bo bontšitse hore li-sensor tsa lifilimi tse tšesaane tsa silevera tse sebelisoang ho 150 ° C ka mokhoa o sa fetoheng oa mocheso li sebetsa hantle bakeng sa ho lekola litaba tsa hydrogen sulfide moeeng oa litoropo.

4. Sensor ea Sulfur Dioxide

Sulfur dioxide ke e ’ngoe ea lintho tse ka sehloohong tse silafatsang moea, ’me ho lemoha sulfur dioxide moeeng ke karolo e tloaelehileng ea tlhahlobo ea moea. Tšebeliso ea li-sensor ho lekola sulfur dioxide e bonts'itse bophahamo bo boholo, ho tloha ho khutsufatsa nako ea ho lemoha ho isa ho theola moeli oa ho lemoha. Li-polymers tse tiileng li sebelisoa e le li-membrane tsa phapanyetsano ea ion, ka lehlakoreng le leng la lera le nang le li-electrolyte tse ka hare bakeng sa k'haontara le li-electrode tsa litšupiso, le electrode ea platinum e kentsoeng ka lehlakoreng le leng ho etsa sensoro ea sulfur dioxide. Sensor e kenngoa ka seleng ea phallo 'me e hlahisa sulfur dioxide ka matla a 0.65V. Ka mor'a moo, ho bontšoa hore na sulphur dioxide e teng hokae. Sesebelisoa sa kutlo se bonts'a kutloisiso e phahameng ea hona joale, nako e khuts'oane ea karabelo, botsitso bo botle, lerata le tlase le tlase, moeli oa 0.2 mmol / L, moeli oa ho lemoha oa 8 * 10-6 mmol / L, le tekanyo ea lerata le lerata. ea 3.

Sensor e ke ke ea lemoha feela sulfur dioxide moeeng, empa hape e ka sebelisoa ho lemoha sulfur dioxide ka metsi a tlaase a conductivity. Sesenthara se sa utloeng ka khase sa sensor ea silika e fetotsoeng ea organically e fetotsoeng ea sulfur dioxide e entsoe ka mokhoa oa sol-gel le theknoloji ea spin. Ho roala hona ho bonts'a ho ikatisa le ho feto-fetoha ho hoholo ha sebabole dioxide, ka nako ea karabo e potlakileng ea metsotsoana e ka tlase ho 20. Ho feta moo, e bonts'a tšebelisano e fokolang le likhase tse ling 'me e susumetsoa hanyane ke liphetoho tsa mocheso le mongobo.