Txoj kev oxidation tshuaj lom neeg yog ib txoj kev ib txwm siv los npaj cov graphite uas nthuav tau. Hauv txoj kev no, cov graphite flake ntuj raug sib xyaw nrog cov tshuaj oxidant thiab cov neeg sawv cev sib xyaw, tswj hwm ntawm qee qhov kub, do tas li, thiab ntxuav, lim thiab ziab kom tau txais cov graphite uas nthuav tau. Txoj kev oxidation tshuaj lom neeg tau dhau los ua ib txoj kev paub tab hauv kev lag luam nrog cov txiaj ntsig ntawm cov khoom siv yooj yim, kev ua haujlwm yooj yim thiab tus nqi qis.
Cov kauj ruam ntawm cov txheej txheem ntawm kev oxidation tshuaj suav nrog oxidation thiab intercalation. Kev oxidation ntawm graphite yog qhov tseem ceeb rau kev tsim cov graphite nthuav dav, vim tias seb qhov kev sib xyaw ua ke puas tuaj yeem ua mus zoo nyob ntawm qib ntawm qhov qhib ntawm cov txheej graphite. Thiab graphite ntuj ntawm chav tsev kub muaj kev ruaj khov zoo heev thiab tiv taus acid thiab alkali, yog li nws tsis cuam tshuam nrog acid thiab alkali, yog li ntawd, kev ntxiv ntawm oxidant tau dhau los ua qhov tseem ceeb hauv kev oxidation tshuaj.
Muaj ntau hom oxidants, feem ntau siv oxidants yog cov khoom oxidants khov (xws li potassium permanganate, potassium dichromate, chromium trioxide, potassium chlorate, thiab lwm yam), kuj tuaj yeem yog qee cov kua oxidizing oxidants (xws li hydrogen peroxide, nitric acid, thiab lwm yam). Nws pom nyob rau hauv xyoo tas los no tias potassium permanganate yog lub oxidant tseem ceeb siv rau hauv kev npaj graphite expandable.
Nyob rau hauv qhov kev ua ntawm oxidizer, graphite yog oxidized thiab cov macromolecules neutral network hauv graphite txheej ua planar macromolecules nrog tus nqi zoo. Vim yog qhov cuam tshuam ntawm tib tus nqi zoo, qhov deb ntawm cov txheej graphite nce ntxiv, uas muab ib txoj hauv kev thiab qhov chaw rau intercalator nkag mus rau hauv graphite txheej du. Hauv cov txheej txheem npaj ntawm expandable graphite, tus neeg sawv cev intercalating feem ntau yog acid. Nyob rau hauv xyoo tas los no, cov kws tshawb fawb feem ntau siv sulfuric acid, nitric acid, phosphoric acid, perchloric acid, mixed acid thiab glacial acetic acid.
Txoj kev siv hluav taws xob electrochemical yog nyob rau hauv ib qho tam sim no tas li, nrog rau cov kua dej ntawm qhov ntxig ua electrolyte, graphite thiab cov ntaub ntawv hlau (cov ntaub ntawv stainless hlau, platinum phaj, txhuas phaj, titanium phaj, thiab lwm yam) tsim ib qho anode sib xyaw, cov ntaub ntawv hlau ntxig rau hauv electrolyte ua cathode, tsim ib lub voj voog kaw; Los yog graphite raug dai rau hauv electrolyte, hauv electrolyte tib lub sijhawm ntxig rau hauv lub phaj tsis zoo thiab zoo, los ntawm ob lub electrodes yog energized txoj kev, anodic oxidation. Qhov chaw ntawm graphite yog oxidized rau carbocation. Tib lub sijhawm, nyob rau hauv kev ua ke ntawm electrostatic attraction thiab concentration sib txawv diffusion, acid ions lossis lwm yam polar intercalant ions raug embedded ntawm cov khaubncaws sab nraud povtseg graphite los tsim cov graphite nthuav dav.
Piv nrog rau txoj kev oxidation tshuaj lom neeg, txoj kev electrochemical rau kev npaj cov graphite nthuav dav hauv tag nrho cov txheej txheem yam tsis siv oxidant, qhov ntau ntawm kev kho mob yog loj, cov khoom seem ntawm cov tshuaj corrosive yog me me, cov electrolyte tuaj yeem rov ua dua tom qab cov tshuaj tiv thaiv, cov kua qaub txo qis, tus nqi txuag tau, kev ua qias tuaj ib puag ncig txo qis, kev puas tsuaj rau cov khoom siv qis, thiab lub neej kev pabcuam ntev dua. Nyob rau hauv xyoo tas los no, txoj kev electrochemical tau maj mam dhau los ua txoj hauv kev nyiam rau kev npaj cov graphite nthuav dav los ntawm ntau lub tuam txhab nrog ntau qhov zoo.
Txoj kev sib kis ntawm cov pa roj yog los tsim cov graphite uas nthuav dav los ntawm kev sib cuag nrog graphite hauv daim ntawv gaseous thiab kev sib xyaw ua ke. Feem ntau, cov graphite thiab cov ntxig tau muab tso rau ntawm ob qho kawg ntawm cov iav tiv taus cua sov, thiab lub tshuab nqus tsev tau pumped thiab kaw, yog li nws kuj hu ua txoj kev ob-chamber. Txoj kev no feem ntau siv los ua cov halide -EG thiab alkali hlau -EG hauv kev lag luam.
Qhov zoo: cov qauv thiab kev txiav txim ntawm lub reactor tuaj yeem tswj tau, thiab cov reactants thiab cov khoom tuaj yeem sib cais tau yooj yim.
Qhov tsis zoo: lub cuab yeej ua teb nyuaj dua, kev ua haujlwm nyuaj dua, yog li cov zis tsawg, thiab cov tshuaj tiv thaiv yuav tsum tau ua nyob rau hauv qhov kub siab, lub sijhawm ntev dua, thiab cov xwm txheej tshuaj tiv thaiv siab heev, qhov chaw npaj yuav tsum yog lub tshuab nqus tsev, yog li tus nqi tsim khoom siab dua, tsis haum rau cov ntawv thov loj.
Txoj kev sib xyaw ua kua yog sib tov cov khoom siv ntxig nrog graphite ncaj qha, nyob rau hauv kev tiv thaiv ntawm kev txav mus los ntawm cov roj inert lossis lub kaw lus kaw rau cua sov ua kom cov tshuaj tiv thaiv los npaj cov graphite nthuav dav. Nws feem ntau yog siv rau kev tsim cov alkali hlau-graphite interlaminar compounds (GICs).
Qhov Zoo: Cov txheej txheem tshuaj tiv thaiv yooj yim, qhov ceev ntawm cov tshuaj tiv thaiv yog ceev, los ntawm kev hloov pauv qhov piv ntawm cov khoom siv graphite raw thiab cov ntxig tuaj yeem ncav cuag qee qhov qauv thiab cov khoom sib xyaw ntawm graphite nthuav dav, tsim nyog dua rau kev tsim khoom loj.
Qhov tsis zoo: Cov khoom tsim tsis ruaj khov, nws nyuaj rau kev daws cov khoom dawb uas txuas rau ntawm qhov chaw ntawm GICs, thiab nws nyuaj rau xyuas kom meej tias cov graphite interlamellar sib xws thaum muaj ntau cov synthesis.
Txoj kev yaj yog sib tov graphite nrog cov khoom siv intercalating thiab cua sov los npaj cov graphite nthuav dav. Raws li qhov tseeb tias cov khoom eutectic tuaj yeem txo qhov melting point ntawm lub kaw lus (qis dua qhov melting point ntawm txhua qhov khoom), nws yog ib txoj hauv kev rau kev npaj cov ternary lossis multicomponent GICs los ntawm kev ntxig ob lossis ntau yam tshuaj (uas yuav tsum muaj peev xwm tsim lub cev ntsev yaj) ntawm cov txheej graphite tib lub sijhawm. Feem ntau siv rau hauv kev npaj cov hlau chlorides - GICs.
Qhov Zoo: Cov khoom tsim tau zoo, yooj yim ntxuav, yooj yim rau kev ua tshuaj tiv thaiv, kub tsawg, lub sijhawm luv luv, tsim nyog rau kev tsim khoom loj.
Qhov tsis zoo: nws nyuaj rau tswj cov qauv kev txiav txim thiab cov khoom sib xyaw hauv cov txheej txheem tshuaj tiv thaiv, thiab nws nyuaj rau xyuas kom meej tias cov qauv kev txiav txim thiab cov khoom sib xyaw hauv cov khoom sib xyaw ua ke.
Txoj kev nias yog sib tov graphite matrix nrog alkaline earth hlau thiab cov hmoov hlau tsis tshua muaj av thiab ua rau M-GICS nyob rau hauv cov xwm txheej nias.
Qhov Tsis Zoo: Tsuas yog thaum lub zog ntawm cov hlau tshaj qhov txwv, qhov kev cuam tshuam ntxig tuaj yeem ua tiav; Txawm li cas los xij, qhov kub siab dhau, yooj yim ua rau hlau thiab graphite tsim cov carbides, kev cuam tshuam tsis zoo, yog li qhov kub ntawm kev cuam tshuam yuav tsum tau tswj hwm hauv qee qhov ntau. Qhov kub ntawm kev ntxig ntawm cov hlau tsis tshua muaj neeg nyob hauv ntiaj teb yog siab heev, yog li yuav tsum tau siv lub siab kom txo qhov kub ntawm kev cuam tshuam. Txoj kev no yog qhov tsim nyog rau kev npaj cov hlau-GICS nrog qhov chaw yaj qis, tab sis lub cuab yeej nyuaj thiab cov kev cai ua haujlwm nruj, yog li nws tsis tshua siv tam sim no.
Feem ntau, txoj kev tawg siv graphite thiab cov neeg sawv cev nthuav dav xws li KClO4, Mg (ClO4) 2 · nH2O, Zn (NO3) 2 · nH2O pyropyros lossis cov khoom sib xyaw uas tau npaj tseg. Thaum nws raug cua sov, graphite yuav ua rau oxidation thiab intercalation sib xyaw ua ke, uas tom qab ntawd nthuav dav hauv txoj kev "tawg", yog li tau txais graphite nthuav dav. Thaum siv cov ntsev hlau ua tus neeg sawv cev nthuav dav, cov khoom muaj ntau yam nyuaj dua, uas tsis yog tsuas yog muaj graphite nthuav dav xwb, tab sis kuj muaj hlau.
