Qhia:
Nyob rau hauv cov ntaub ntawv science,titanium dioxide(TiO2) tau tshwm sim los ua ib qho chaw zoo nkauj nrog ntau yam kev siv. Cov khoom sib xyaw no muaj cov khoom siv tshuaj lom neeg thiab lub cev zoo heev, ua rau nws muaj nuj nqis hauv ntau qhov chaw lag luam. Yuav kom nkag siab txog nws qhov tshwj xeeb zoo, titanium dioxide tus qauv ntxim nyiam yuav tsum tau kawm hauv qhov tob. Hauv tsab ntawv blog no, peb yuav tshawb xyuas cov qauv ntawm titanium dioxide thiab tso lub teeb rau ntawm cov laj thawj tseem ceeb tom qab nws cov khoom tshwj xeeb.
1. Crystal qauv:
Titanium dioxide muaj cov qauv siv lead ua, txiav txim siab feem ntau los ntawm nws qhov tshwj xeeb ntawm cov atoms. Txawm tiasTiO 2muaj peb theem crystalline (anatase, rutile, thiab brookite), peb yuav tsom mus rau ob hom ntau tshaj plaws: rutile thiab anatase.
A. Rutile Structure:
Lub rutile theem yog paub txog nws tetragonal siv lead ua qauv, nyob rau hauv uas txhua titanium atom yog surrounded los ntawm rau oxygen atoms, tsim ib tug twisted octahedron. Qhov kev npaj no tsim ib txheej atomic ntom ntom nrog cov txheej txheem oxygen kaw. Cov qauv no muab rutile exceptional stability thiab durability, ua rau nws haum rau ntau yam kev siv, nrog rau cov xim, ceramics, thiab txawm sunscreen.
B. Anatase qauv:
Nyob rau hauv cov ntaub ntawv ntawm anatase, titanium atoms yog sib koom ua ke rau tsib oxygen atoms, tsim octahedrons uas sib koom npoo. Yog li ntawd, qhov kev npaj no ua rau cov qauv qhib ntau dua nrog tsawg dua atoms ib chav tsev ntim piv rau rutile. Txawm hais tias nws qis ntom ntom, anatase cov ntawv pov thawj zoo cov duab photocatalytic zoo nkauj, ua kom muaj cov yees duab huab cua thiab ntxuav cov txheej txheem huab cua thiab ntxuav cov txheej txheem ua kom huv.
2. Lub zog band sib txawv:
Lub zog band sib txawv yog lwm yam tseem ceeb ntawm TiO2 thiab pab txhawb rau nws cov khoom tshwj xeeb. Qhov sib txawv no txiav txim siab cov khoom siv hluav taws xob conductivity thiab nws qhov rhiab heev rau lub teeb haum.
A. Rutile band qauv:
Rutile TiO2muaj qhov sib txawv ntawm qhov nqaim ntawm kwv yees li 3.0 eV, ua rau nws tsis muaj hluav taws xob tsawg. Txawm li cas los xij, nws cov qauv band tuaj yeem nqus tau ultraviolet (UV) lub teeb, ua rau nws zoo tagnrho rau kev siv tshuaj tiv thaiv UV xws li tshuaj pleev thaiv hnub.
B. Anatase band qauv:
Anatase, ntawm qhov tod tes, nthuav dav qhov sib txawv ntawm kwv yees li 3.2 eV. Cov yam ntxwv no muab anatase TiO2 zoo heev photocatalytic kev ua haujlwm. Thaum raug lub teeb, electrons nyob rau hauv lub valence band zoo siab thiab dhia mus rau hauv lub conduction band, ua rau muaj ntau yam oxidation thiab txo cov tshuaj tiv thaiv tshwm sim. Cov khoom no qhib lub qhov rooj rau cov ntawv thov xws li kev lim dej thiab kev txo cov pa phem.
3. Qhov tsis zoo thiab kev hloov kho:
Covstructure of Tio2tsis yog tsis muaj flaws. Cov kev tsis zoo thiab kev hloov kho no cuam tshuam rau lawv lub cev thiab tshuaj lom neeg.
A. Oxygen vacancy:
Qhov tsis xws luag nyob rau hauv daim ntawv ntawm cov pa oxygen vacancies nyob rau hauv lub TiO2 lattice qhia ib tug concentration ntawm unpaired electrons, ua rau muaj zog catalytic kev ua si thiab tsim cov xim chaw.
B. Nto hloov kho:
Kev hloov kho saum npoo, xws li doping nrog lwm cov hlau ions hloov pauv lossis ua haujlwm nrog cov organic sib txuas, tuaj yeem txhim kho qee yam khoom ntawm TiO2. Piv txwv li, doping nrog hlau xws li platinum tuaj yeem txhim kho nws cov catalytic kev ua tau zoo, thaum cov organic ua haujlwm pab pawg tuaj yeem txhim kho cov khoom ruaj khov thiab photoactivity.
Hauv kev xaus:
Kev nkag siab txog cov qauv txawv txawv ntawm Tio2 yog qhov tseem ceeb rau kev nkag siab txog nws cov khoom zoo kawg nkaus thiab ntau yam kev siv. Txhua daim ntawv crystalline ntawm TiO2 muaj cov khoom tshwj xeeb, los ntawm cov qauv tetragonal rutile mus rau qhov qhib, photocatalytically nquag nquag anatase theem. Los ntawm kev tshawb nrhiav lub zog ntawm qhov sib txawv thiab qhov tsis xws luag hauv cov ntaub ntawv, cov kws tshawb fawb tuaj yeem ua kom zoo dua lawv cov khoom rau cov ntawv thov xws li kev ua kom huv mus rau kev sau lub zog. Raws li peb txuas ntxiv mus nthuav tawm qhov tsis meej ntawm titanium dioxide, nws lub peev xwm hauv kev lag luam kiv puag ncig tseem muaj kev cia siab.
Post lub sij hawm: Oct-30-2023