Graphite yakakamurwa kuita artificial graphite uye natural graphite, iyo pasi rose inopupurirwa matura echisikigo graphite mumatani anosvika mabhiriyoni maviri.
Artificial graphite inowanikwa nekuparara uye kupisa kwekupisa kwezvinhu zvine kabhoni pasi pekumanikidzwa kwakajairwa.Shanduko iyi inoda tembiricha yakakwana uye simba sesimba rekutyaira, uye chimiro chakakanganisika chinoshandurwa kuita yakarongedzerwa graphite crystal chimiro.
Graphitization iri mune yakafara pfungwa yezvinhu kabhoni kuburikidza nepamusoro pe2000 ℃ yakanyanya tembiricha yekupisa kupisa kabhoni maatomu rearrangement, zvisinei mamwe kabhoni ari mutembiricha yepamusoro pamusoro pe3000 ℃ graphitization, rudzi urwu rwekabhoni rwaizivikanwa se "marasha akaomarara", ye nyore graphitized kabhoni zvinhu, iyo yechinyakare graphitization nzira inosanganisira yakakwira tembiricha uye yakanyanya kudzvanywa nzira, catalytic graphitization, kemikari vapor deposition nzira, nezvimwe.
Graphitization inzira inoshanda yekuwedzera kukosha kwekushandisa kwezvinhu zvekabhoni.Mushure mekutsvagisa kwakadzama uye kwakadzama nenyanzvi, yatokura izvozvi.Nekudaro, zvimwe zvinhu zvisingafadzi zvinomisa kushandiswa kwechinyakare graphitization muindasitiri, saka itsika isingadzivisike yekuongorora nzira nyowani dzegraphitization.
Yakanyungudutswa munyu electrolysis nzira kubvira muzana remakore rechi19 akanga anopfuura zana kukura, ayo nheyo nheyo uye nzira itsva anogara utsanzi uye budiriro, iye zvino haichagumiri echinyakare metallurgical indasitiri, pakutanga kwezana remakore rechi21, simbi mu iyo yakanyungudutswa munyu system solid oxide electrolytic kuderedza gadziriro ye elemental simbi yave iyo yekutarisa mune yakanyanya kushanda,
Munguva ichangopfuura, nzira itsva yekugadzira magirafu zvinhu neyakanyungudutswa munyu electrolysis yakwezva vanhu vakawanda.
Nenzira ye cathodic polarization uye electrodeposition, iyo miviri yakasiyana-siyana ye carbon raw materials inoshandurwa kuita nano-graphite zvinhu zvine kukosha kwakawedzerwa.Kuenzaniswa neyechinyakare graphitization tekinoroji, iyo itsva graphitization nzira ine zvakanakira yakaderera graphitization tembiricha uye controllable morphology.
Iri bepa rinoongorora kufambira mberi kwegraphitization ne electrochemical nzira, inosuma iyi tekinoroji nyowani, inoongorora zvayakanakira nezvayakaipira, uye inotarisira maitiro ayo emangwana ebudiriro.
Kutanga, yakanyungudutswa munyu electrolytic cathode polarization nzira
1.1 iyo mbishi zvinhu
Parizvino, iyo huru yezvigadzirwa zveartificial graphite ndeye tsono coke uye pitch coke yemhando yepamusoro graphitization degree, iyo yakasara yemafuta uye marasha tara seyakagadzirwa kugadzira yakakwira mhando kabhoni, ine yakaderera porosity, yakaderera sarufa, yakaderera dota. zvemukati uye zvakanakira graphitization, mushure mekugadzirira kwayo kuita graphite ine kumira kwakanaka kunokanganisa, yakakwira mechini simba, yakaderera resistivity,
Nekudaro, mashoma emafuta akachengetwa uye mitengo yemafuta iri kudonha yakaganhurira kukura kwayo, saka kutsvaga zvigadzirwa zvitsva rave dambudziko rekukurumidza kugadziriswa.
Nzira dzechinyakare dze graphitization dzine zvisingakwanisi, uye nzira dzakasiyana dze graphitization dzinoshandisa zvinhu zvakasiyana-siyana.Kune isina-graphitized kabhoni, nzira dzechinyakare hadzigone kuita graphitize, nepo electrochemical formula yeyakanyungudutswa munyu electrolysis inotyora nekudzikiswa kwezvinhu, uye inokodzera zvinenge zvese zvechinyakare kabhoni zvinhu.
Zvechinyakare kabhoni zvinhu zvinosanganisira kabhoni dema, activated kabhoni, marasha, nezvimwewo, pakati peiyo marasha ndiyo inonyanya kuvimbisa.Iyo inki-yakavakirwa marasha inotora marasha seanotangira uye inogadzirirwa kuita zvigadzirwa zvegraphite pakupisa kwakanyanya mushure mekutanga kurapwa.
Munguva ichangopfuura, bepa rino rinokurudzira nzira itsva dze electrochemical, dzakadai sePeng, neyakanyungudutswa munyu electrolysis haigone graphitized kabhoni dema mune yakakwira crystallinity yegraphite, iyo electrolysis yemagraphite samples ine petal shape graphite nanometer chips, ine yakakwirira chaiyo nzvimbo, payakashandiswa lithium bhatiri cathode yakaratidza yakanakisa electrochemical kuita kupfuura yakasikwa graphite.
Zhu et al.akaisa marasha anouraya akadzikiswa akaderera-mhando muCaCl2 yakanyungudutswa munyu system ye electrolysis pa 950 ℃, uye yakabudirira kushandura yakaderera-mhando marasha kuita graphite ine yakakwira crystallinity, iyo yakaratidza kuita kwakanaka kwekuita uye hupenyu hurefu hwekutenderera payakashandiswa seanode ye lithium ion bhatiri. .
Kuedza kwacho kunoratidza kuti zvinokwanisika kushandura mhando dzakasiyana dzechinyakare kabhoni kuita graphite nenzira yakanyungudutswa yemunyu electrolysis, iyo inovhura nzira nyowani yeramangwana rekugadzira graphite.
1.2 nzira ye
Melten salt electrolysis method inoshandisa kabhoni secathode uye inoishandura kuita graphite ine high crystallinity nenzira ye cathodic polarization.Parizvino, mabhuku aripo anotaura nezvekubviswa kweokisijeni uye kureba kurebazve kwekabhoni maatomu mune inogona kutendeuka nzira ye cathodic polarization.
Kuvapo kweokisijeni mune kabhoni zvinhu kunotadzisa graphitization kune imwe nhanho.Muchinyakare graphitization process, okisijeni inozobviswa zvishoma nezvishoma kana tembiricha yakakwira kupfuura 1600K.Nekudaro, zvakanyanya nyore kuita deoxidize kuburikidza necathodic polarization.
Peng, nezvimwewo mukuedza kekutanga kuisa pamberi yakanyungudutswa munyu electrolysis cathodic polarization inogona mashandiro, kureva graphitization kazhinji nzvimbo yekutanga ichave iri mune yakasimba kabhoni microspheres/electrolyte interface, yekutanga kabhoni microsphere fomu yakatenderedza dhayamita imwechete. graphite shell, uyezve haizombogadzika anhydrous carbon maatomu ekabhoni akapararira kune yakagadzikana yekunze graphite flake, kusvika yazara graphitized,
Iyo graphitization process inoperekedzwa nekubviswa kweokisijeni, iyo inosimbiswa zvakare nemiedzo.
Jin et al.yakaratidzawo pfungwa iyi kuburikidza nekuedza.Mushure mecarbonization yeglucose, graphitization (17% okisijeni yemukati) yakaitwa.Mushure me graphitization, iyo yepakutanga yakasimba carbon spheres (Fig. 1a uye 1c) yakagadzira ganda rinoputika rinoumbwa ne graphite nanosheets (Fig. 1b uye 1d).
Ne electrolysis yekabhoni fibers (16% okisijeni), iyo kabhoni fibers inogona kushandurwa kuita graphite machubhu mushure me graphitization maererano neshanduko nzira inofungidzirwa mumabhuku.
Zvinotendwa kuti, rwendo rurefu rwuri pasi pe cathodic polarization yekabhoni maatomu iyo yakakwira crystal graphite kune amorphous kabhoni rearrange inofanirwa kugadzirisa, yekugadzira graphite yakasarudzika petals chimiro nanostructures inobatsirwa nemaatomu eokisijeni kubva, asi iyo chaiyo nzira yekukanganisa graphite nanometer chimiro haina kujeka, zvakadai seokisijeni kubva kabhoni skeleton mushure mekuita sei pa cathode reaction, nezvimwewo,
Parizvino, kutsvagisa pamusoro pemashini kuchiri padanho rekutanga, uye kumwe kutsvagisa kunodiwa.
1.3 morphological maitiro ekugadzira graphite
SEM inoshandiswa kuona iyo microscopic surface morphology yegraphite, TEM inoshandiswa kutarisa morphology yemaitiro isingasviki 0.2 μm, XRD uye Raman spectroscopy ndiyo inonyanya kushandiswa nzira kuratidza microstructure yegraphite, XRD inoshandiswa kuratidza kristaro. ruzivo rwegraphite, uye Raman spectroscopy inoshandiswa kuratidza kukanganisa uye kurongeka dhigirii regraphite.
Kune akawanda ma pores mu graphite yakagadzirwa ne cathode polarization ye yakanyungudutswa munyu electrolysis.Kune akasiyana mbizha, senge kabhoni nhema electrolysis, petal-senge porous nanostructures inowanikwa.XRD uye Raman spectrum ongororo inoitwa pane kabhoni nhema mushure me electrolysis.
Pa827 ℃, mushure mekurapwa ne 2.6V voltage ye 1h, mufananidzo weRaman wekabhoni dema wakada kufanana newekutengesa graphite.Mushure mekunge kabhoni dema yabatwa nekudziya kwakasiyana, iyo inopinza graphite maitiro peak (002) inoyerwa.Iyo diffraction peak (002) inomiririra dhigirii rekutarisa kweiyo inonhuhwirira kabhoni layer mugraphite.
Iyo yakanyanya kupinza kabhoni layer, iyo yakanyanya kutariswa.
Zhu akashandisa marasha akacheneswa akaderera secathode mukuedza, uye microstructure yechigadzirwa chegirati yakashandurwa kubva kugranular kusvika kuhombe yegirafu chimiro, uye girafu rakaomarara rakaonekwawo pasi peyepamusoro-soro yekufambisa maikorosikopu.
MuRaman spectra, neshanduko yemamiriro ekuyedza, iyo ID/Ig kukosha yakachinjawo.Apo tembiricha ye electrolytic yaive 950 ℃, nguva ye electrolytic yaive 6h, uye electrolytic voltage yaive 2.6V, yakaderera ID/Ig kukosha yaive 0.3, uye D peak yaive yakaderera zvakanyanya pane G peak.Panguva imwecheteyo, kutaridzika kwe2D peak zvakare kwakamiririra kuumbwa kweiyo yakanyanya kurongeka graphite chimiro.
Iyo inopinza (002) diffraction peak mumufananidzo weXRD inosimbisawo kubudirira kushandurwa kwemarasha akaderera kuita graphite ine yakakwirira crystallinity.
Muchirongwa chegraphitization, kuwedzera kwekushisa uye voltage kuchaita basa rekusimudzira, asi yakawandisa voltage inoderedza goho regraphite, uye yakanyanya tembiricha kana nguva yakareba yegraphitization inotungamira mukuraswa kwezvinhu, saka kune akasiyana kabhoni zvinhu. , inonyanya kukosha kuti uongorore zvakanyanya zvakakodzera electrolytic mamiriro, ihwowo kutarisa uye kuoma.
Iyi petal-senge flake nanostructure ine yakanakisa electrochemical zvimiro.Nhamba huru ye pores inobvumira ions kuti ikurumidze kuiswa / kuvharwa, ichipa yakakwirira-yepamusoro cathode zvinhu zvemabhatiri, nezvimwe.
Yakanyungudutswa munyu electrodeposition nzira
2.1 Electrodeposition yecarbon dioxide
Seyakanyanya kukosha gasi regreenhouse, CO2 zvakare isiri-chepfu, isingakuvadzi, yakachipa uye inowanikwa zviri nyore renewable sosi.Nekudaro, kabhoni iri muCO2 iri munzvimbo yepamusoro oxidation, saka CO2 ine yakakwira thermodynamic kugadzikana, izvo zvinoita kuti zviome kushandisa zvakare.
Tsvagiridzo yekutanga paCO2 electrodeposition inogona kurondwa kumashure kuma1960s.Ingram et al.zvakabudirira kugadzirira kabhoni pane electrode yegoridhe mune yakanyungudutswa munyu system yeLi2CO3-Na2CO3-K2CO3.
Van et al.yakaratidza kuti kabhoni poda yakawanikwa pamhando dzakasiyana dzekudzikisa yaive nezvimiro zvakasiyana, zvinosanganisira graphite, amorphous kabhoni uye kabhoni nanofibers.
Nemunyu wakanyungudutswa kutora CO2 uye nzira yekugadzirira yekubudirira kwekabhoni, mushure menguva yakareba yekutsvagisa nyanzvi dzakatarisa pane kabhoni deposition kuumbwa meshini uye mhedzisiro yemamiriro e electrolysis pachigadzirwa chekupedzisira, izvo zvinosanganisira tembiricha ye electrolytic, electrolytic voltage uye kuumbwa kwe. munyu wakanyungudutswa uye maelectrodes, nezvimwewo, kugadzirira kwepamusoro pekuita kwe graphite zvinhu zve electrodeposition ye CO2 yakaisa hwaro hwakasimba.
Nekushandura electrolyte uye kushandisa CaCl2-yakanyungudutswa munyu system ine yakakwira CO2 kutora kunyatsoita, Hu et al.zvakabudirira kugadzirira graphene ine yepamusoro graphitization dhigirii uye kabhoni nanotubes uye zvimwe zvimiro zvenanographite nekudzidza electrolytic mamiriro senge electrolysis tembiricha, electrode kuumbwa uye yakanyungudutswa munyu.
Kana ichienzaniswa necarbonate system, CaCl2 ine zvakanakira zvekuchipa uye zviri nyore kuwana, yakakwirira conductivity, nyore kunyungudika mumvura, uye yakanyanya kunyungudika yeokisijeni ion, iyo inopa mamiriro edzidziso yekushandurwa kweCO2 kuita zvigadzirwa zvegraphite zvine kukosha kwakawedzera.
2.2 Shanduko Mechanism
Kugadzirira kwepamusoro-yakawedzerwa kabhoni zvinhu ne electrodeposition yeCO2 kubva munyu yakanyungudutswa inonyanya kusanganisira CO2 kubatwa uye kuderedzwa kusina kunanga.Kutorwa kweCO2 kunopedzwa nemahara O2- mumunyu wakanyungudutswa, sezvinoratidzwa muEquation (1) :
CO2+O2-→CO3 2- (1)
Parizvino, nzira nhatu dzisina kunanga dzekudzikisa maitiro dzakatsanangurwa: nhanho imwe-nhanho, maviri-nhanho maitiro uye simbi yekudzikisa maitiro maitiro.
Iyo nhanho-yekuita maitiro yakatanga kukurudzirwa naIngram, sezvakaratidzwa muEquation (2):
CO3 2-+ 4E – →C+3O2- (2)
Maitiro maviri-matanho ekuita akakurudzirwa naBorucka et al., sezvakaratidzwa muEquation (3-4) :
CO3 2-+ 2E – →CO2 2-+O2- (3)
CO2 2-+ 2E – →C+2O2- (4)
Iyo nzira yekudzikisa simbi yekuita yakatsanangurwa naDeanhardt et al.Vaitenda kuti iyoni yesimbi yakatanga kuderedzwa kuita simbi mu cathode, uyezve simbi yakaderedzwa kuita carbonate ion, sezvinoratidzwa muEquation (5~6) :
M- + E – →M (5)
4 m + M2CO3 – > C + 3 m2o (6)
Parizvino, danho rimwe rekuita maitiro rinowanzogamuchirwa mumabhuku aripo.
Yin et al.akadzidza Li-Na-K carbonate system ine nickel se cathode, tin dioxide seanode uye sirivheri waya sereferensi electrode, uye akawana iyo cyclic voltammetry test figure iri muFigure 2 (scanning rate ye100 mV/s) pa nickel cathode, ndokuwana. kuti paingova nepamusoro pekudzikisa kumwe chete (pa -2.0V) mukutarisisa kwakashata.
Nokudaro, zvinogona kugumiswa kuti chiitiko chimwe chete chakaitika panguva yekuderedza carbonate.
Gao et al.yakawana yakafanana cyclic voltammetry mune imwechete carbonate system.
Get et al.yakashandisa inert anode uye tungsten cathode kutora CO2 muLiCl-Li2CO3 system uye yakawana mifananidzo yakafanana, uye chete kuderedzwa kwepamusoro kwekabhoni deposition kwakaonekwa mune yakaipa scanning.
Mune alkaline simbi yakanyungudutswa munyu system, alkali simbi uye CO inogadzirwa uku kabhoni ichiiswa necathode.Nekudaro, nekuti iyo thermodynamic mamiriro eiyo kabhoni deposition reaction yakadzikira pane yakaderera tembiricha, chete kudzikiswa kwecarbonate kuita kabhoni ndiko kunoonekwa mukuyedza.
2.3 CO2 inobatwa nemunyu wakanyungudutswa kugadzira zvigadzirwa zvegraphite
High-value-added graphite nanomaterials senge graphene uye kabhoni nanotubes inogona kugadzirwa ne electrodeposition ye CO2 kubva mumunyu wakanyungudutswa nekudzora mamiriro ekuedza.Hu et al.yakashandisa simbi isina simbi se cathode muCaCl2-NaCl-CaO yakanyungudutswa munyu system uye yakanyungudutswa nemagetsi kwe4h pasi pemamiriro e2.6V anogara ari voltage pakudziya kwakasiyana.
Kutenda kune catalysis yesimbi uye kuputika kweCO pakati pegraphite layers, graphene yakawanikwa pamusoro pecathode.Nzira yekugadzirira yegraphene inoratidzwa mumufananidzo 3.
Mufananidzo
Gare gare zvidzidzo zvakawedzera Li2SO4 pahwaro hweCaCl2-NaClCaO yakanyungudutswa munyu system, tembiricha ye electrolysis yaive 625 ℃, mushure me4h ye electrolysis, panguva imwechete mu cathodic deposition yecarbon yakawana graphene uye kabhoni nanotubes, chidzidzo chakawana kuti Li + uye SO4 2. - kuunza mhedzisiro yakanaka pane graphitization.
Sulfur inobatanidzwawo zvakabudirira mumutumbi wecarbon, uye ultra-thin graphite sheets uye filamentous carbon inogona kuwanikwa nekudzora mamiriro e electrolytic.
Zvinhu zvakadai se electrolytic tembiricha yekumusoro uye yakaderera pakuumbwa kwegraphene yakakosha, kana tembiricha yakakwira kupfuura 800 ℃ iri nyore kugadzira CO pachinzvimbo chekabhoni, inenge isina kabhoni deposition kana yakakwira kupfuura 950 ℃, saka tembiricha yakakosha zvakanyanya. kugadzira graphene uye kabhoni nanotubes, uye kudzoreredza chinodiwa kabhoni deposition reaction CO reaction synergy kuona kuti cathode inogadzira yakagadzikana graphene.
Aya mabasa anopa nzira itsva yekugadzirira kwe nano-graphite zvigadzirwa neCO2, iyo inokosha zvikuru yekugadzirisa magasi egreenhouse uye kugadzirira graphene.
3. Pfupiso uye Outlook
Nekukurumidza kukura kweindasitiri yemagetsi matsva, magirafu echisikigo haana kukwanisa kuzadzisa kudiwa kwazvino, uye girafu yekugadzira ine zviri nani zvemuviri uye kemikari zvivakwa kupfuura girafu yechisikigo, saka zvakachipa, zvinobudirira uye zvakatipoteredza graphitization chinangwa chenguva refu.
Electrochemical ways graphitization in solid and gaseous raw materials ine nzira ye cathodic polarization uye electrochemical deposition yakabudirira kubuda mu graphite zvinhu zvine high value yakawedzerwa, zvichienzaniswa nemaitiro echinyakare egraphitization, nzira ye electrochemical ndeyekunyanya kushanda, kuderera kwesimba rekushandisa. kuchengetedzwa kwegirinhi kwezvakatipoteredza, kune zvidiki zvakaganhurirwa nezvinhu zvakasarudzwa panguva imwe chete, zvinoenderana neyakasiyana electrolysis mamiriro anogona kugadzirirwa pane akasiyana morphology yegraphite chimiro,
Inopa nzira inoshanda kune ese marudzi eamorphous kabhoni uye greenhouse magasi kuti ashandurwe kuita akakosha nano-yakarongeka graphite zvinhu uye ine yakanaka application tarisiro.
Parizvino, tekinoroji iyi ichiri kutanga.Kune zvishoma zvidzidzo zve graphitization ne electrochemical nzira, uye kuchine akawanda asingazivikanwe maitiro.Naizvozvo, zvinodikanwa kuti utange kubva kune zvigadzirwa uye kuita chidzidzo chakazara uye chakarongeka pane akasiyana amorphous kabhoni, uye panguva imwechete kuongorora iyo thermodynamics uye dynamics yekutendeuka kwegraphite mune yakadzika nhanho.
Izvi zvine kukosha kukuru kune ramangwana rekusimudzira indasitiri yegraphite.
Nguva yekutumira: May-10-2021