Lapho izingqimba ze-graphene zinamathiselwe phezu kwesinye, zakha i-graphite. Imilimitha eyodwa yegraphite iqukethe izendlalelo ezingaba yizigidi ezi-3 zegraphene. Ipensela elincane ephepheni lishiya imikhondo engase ibe izendlalelo ezimbalwa noma ungqimba olulodwa lwe-graphene. Ngenxa yesakhiwo sayo{4}}esihle kakhulu esinezinhlangothi ezimbili, sisebenza njengesengezo esisebenzayo emikhiqizweni eminingi emisha.
Uma kukhulunywa nge-graphene, okukhulunywe ngakho okudume kakhulu ngokungangabazeki uMklomelo kaNobel we-Physics ka-2010, okwabelwana ngawo ososayensi ababili ngocwaningo lwabo olunesisekelo nge-graphene. Muva nje, i-Fudan University imemezele ukuthi abacwaningi bayo, ngokubambisana nalabo abavela ku-National University of Singapore, basungule{2}}indlela entsha,{3}}esebenza kahle kakhulu yokulungiselela i-graphene ubuchwepheshe bayo obuyisisekelo bungakhuliswa kalula ukuze kukhiqizwe izimboni.
Ngokuphawulekayo, ithimba labacwaningi lathatha indlela ephambene ngokuphelele nendlela evamile yokushicilela amaphepha kuqala bese lisebenzisana namabhizinisi. Bathole imiphumela emisha ngo-2013, bafaka ilungelo lobunikazi ngo-2014, badlulisela ilungelo lobunikazi ebhizinisini lasekhaya ngo-2015, futhi bashicilela kuphela abakutholile ku-inthanethiUkuxhumana Kwemvelongo-January 8. U-Lu Hongbin, omunye wabaholi beqembu abavela eMnyangweni Wezesayensi Yezinto Ezinkulu kanye ne-State Key Laboratory ye-Molecular Engineering of Polymers eFudan University, wathi ngokumomotheka: “Izinto ezinhle zikufanele ukulinda; ngokuvamile ziba ngcono ngemva kwesikhathi esithile ukuze zivuthwe.”
Isithombe se-atomic-resolution electron microscopy (a), i-Raman spectrum (b), i-X-ray photoelectron spectroscopy spectrum (c), kanye nesithombe esikhulu se-atomic force microscopy (d) se-graphene njengoba-elungiselelwe; iziqephu zokusabalalisa ukujiya kwe-graphene (e) kanye nezibalo zosayizi basemaceleni (f).
Isithombe ngu-Dong Lei
Bambalwa abantu abaqaphelayo ukuthi i-graphene akulona nje igama elisohlwini lwemiklomelo kaNobel - isivele ihlanganiswe eduze nokuphila kwansuku zonke. Ikhona ngokwemvelo emhlabeni, nakuba ukuhlukanisa-i-graphene eyodwa akuwona umsebenzi olula. Isendlalelo esistakiwe ngokwesendlalelo, i-graphene yakha i-graphite, enemilimitha engu-1 yegraphite equkethe cishe izendlalelo zegraphene eziyizigidi ezi-3. Uphawu lwepensela ephepheni lungaba eziningana noma ngisho nongqimba olulodwa lwe-graphene. Ngenxa yesakhiwo sayo esihle se-2D, isebenza njengesengezo esisebenzayo emikhiqizweni emisha ehlukahlukene:
· Ingezwe embotsheni ye-polymer ekhethekile, inweba impilo yesevisi ngokusebenzisa izakhiwo ezinhle kakhulu zokuthibela;
· Isetshenziswa njenge-ejenti ye-conductive kumabhethri, ukwakheka kwayo kwe-2D kusiza ukuthuthwa kwe-electron ngokushesha, kukhuphule kakhulu isivinini sokushaja;
· Ifakwe kumafayibha kanye nezinto zokushisisa zikagesi, ukuqhutshwa kwayo okukhethekile kukagesi kanye ne-thermal kuthuthukisa ukusebenza komkhiqizo kakhulu.
Uma kubhekwa ukubaluleka kwayo okukhulu, izindlela ezingcono zokulungiselela seziphenduke umgomo wokuncintisana kuzo zombili izifundiswa nezimboni. Ososayensi ababili eNyuvesi yaseManchester - u-Andre Geim kanye no-Konstantin Novoselov - bathola indlela elula ngokuphawulekayo yokuthola ama-graphite flakes aya ngokuya azaca. Bahluba ama-flakes avela ku-pyrolytic graphite egxile kakhulu, banamathisele izinhlangothi zombili ku-tape ekhethekile yokunamathisela, futhi bahlukanise ama-flakes ngokuklebhula itheyiphu. Ukuphinda le nqubo kwaveza amashidi azacile futhi aba mancane, ekugcineni kwaholela kuma-flakes akhiwe ungqimba olulodwa nje lwama-athomu e-carbon: i-graphene. Kusukela lapho, kuye kwavela izindlela eziningi ezintsha zokulungiselela, futhi ngemva kweminyaka emihlanu yokuthuthuka, ukukhiqizwa kwezimboni{6}} kwe-graphene sekufinyeleleke.
USolwazi Lu Hongbin unikeze igraphene izihloko ezintathu "ezingcono kakhulu emhlabeni":
· I-thinnest material eyaziwayo, enobukhulu obungama-nanometer angu-0.335 kuphela;
· Izinto eziqine kakhulu, ziqine izikhathi eziyikhulu kunensimbi;
·I-conductor engcono kakhulu eshisayo, ephakeme izikhathi ezingaphezu kwezingu-10 kunesiliva.
Ngaphezu kwalokho, i-graphene inokuhamba kwama-electron aphezulu kakhulu, ama-oda amabili obukhulu aphakeme kune-silicon. Njengento ebalulekile evelayo yamasu, le noveli ye-2D inamandla amakhulu okusebenza kumishini ehlakaniphile, i-aerospace, ukugcinwa kwamandla, ukulungiswa kwemvelo, neminye imikhakha eminingi.
Kodwa-ke, ukuzuza ukukhiqizwa-okusezingeni eliphezulu{1}kwekhwalithi ephezulu sekuyisikhathi eside kuyingqinamba evimbela ukusetshenziswa kwayo okusabalele.
I-graphene ikhona ngokwemvelo, futhi isu elilungile lokulungiselela ukucwenga i-graphite ye-flake yemvelo ibe yi-graphene ku-solvent ethile yoketshezi. Ngamanye amazwi, njengoba i-graphene i-hydrophobic, inani elikhulu lama-surfactants kufanele lifakwe oketshezini ngesikhathi sokuxoshwa, ngaphandle kwalokho ukuhlukana cishe akunakwenzeka. Izindlela ezivamile ngokuvamile zidinga amathani angu-3 wama-oxidants njenge-potassium permanganate ukuze kukhiqizwe ithani elingu-1 le-graphene, liyiguqule libe yi-graphene oxide ngaphambi kokusikhipha kanye nokunciphisa. Le nqubo ikhiqiza umthamo omkhulu wamanzi angcolile asuka ku-oxidation, ekwehliseni, nasekuhlanzweni, kuyilapho futhi yehlisa isithunzi sezinto ezithile eziyingqayizivele ze-graphene.
Ithimba labacwaningi lizinqobe kanjani lezi zinselele?Lamukele isu lokuhlakazeka elingazinzile ngokwethula inani elincane kakhulu le-ionzable oxygen{0}}eliqukethe amaqembu asebenzayo endaweni ye-graphene, evumela ukucwiliswa okusheshayo,{1}}okunesivuno esikhulu ngokugxilisa kakhulu{2}okuphezulu. Ngaphezulu kuka-90% womkhiqizo osuliwe uyi-graphene yongqimba eyodwa-enobuthakathaka obuncane be-lattice, ixazulula ngokuphumelelayo izinkinga zesitoreji nezokuthutha zezinhlelo zokusebenza ezinkulu-. Ngaphezu kwalokho, i-aqueous graphene slurry ekhiqizwa yile ndlela ibonisa izici ezinhle ze-rheological futhi ingasetshenziswa ngokuqondile ukuze i-3D{9}iphrinte ama-graphene aerogels anomumo ohlukahlukene, ivule izindlela ezintsha zokusetshenziswa kwe-graphene ekugcineni amandla, ukwelashwa kwemvelo, izinhlanganisela zemisebenzi eminingi, nangaphezulu.
