Xyoo 2010, Geim thiab Novoselov yeej qhov khoom plig Nobel hauv physics rau lawv txoj haujlwm ntawm graphene. Qhov khoom plig no tau tso ib qho kev xav tob rau ntau tus neeg. Tom qab tag nrho, tsis yog txhua yam cuab yeej sim Nobel Prize zoo li daim kab xev nplaum, thiab tsis yog txhua yam khoom tshawb fawb zoo li khawv koob thiab yooj yim to taub zoo li "ob-seem siv lead ua" graphene. Txoj haujlwm hauv xyoo 2004 tuaj yeem muab rau xyoo 2010, uas tsis tshua muaj nyob rau hauv cov ntaub ntawv ntawm Nobel Prize hauv xyoo tas los no.
Graphene yog ib hom khoom uas muaj ib txheej ntawm cov pa roj carbon atoms uas sib dhos ua ke zoo li lub lattice honeycomb hexagonal ob-seem. Zoo li pob zeb diamond, graphite, fullerene, carbon nanotubes thiab amorphous carbon, nws yog ib yam khoom (yam yooj yim) uas muaj cov ntsiab lus carbon. Raws li pom hauv daim duab hauv qab no, fullerenes thiab carbon nanotubes tuaj yeem pom tias dov ua ib txoj hauv kev los ntawm ib txheej ntawm graphene, uas tau teeb tsa los ntawm ntau txheej ntawm graphene. Kev tshawb fawb theoretical ntawm kev siv graphene los piav qhia txog cov khoom ntawm ntau yam carbon yooj yim (graphite, carbon nanotubes thiab graphene) tau kav ntev li 60 xyoo, tab sis feem ntau ntseeg tias cov khoom siv ob-seem no nyuaj rau nyob ruaj khov ib leeg, tsuas yog txuas rau qhov chaw peb-seem lossis sab hauv cov khoom xws li graphite. Nws tsis yog txog xyoo 2004 uas Andre Geim thiab nws tus tub ntxhais kawm Konstantin Novoselov tau tshem tawm ib txheej ntawm graphene los ntawm graphite los ntawm kev sim uas kev tshawb fawb ntawm graphene tau ua tiav kev txhim kho tshiab.
Ob qho tib si fullerene (sab laug) thiab carbon nanotube (nruab nrab) tuaj yeem suav tias yog dov los ntawm ib txheej ntawm graphene hauv qee txoj kev, thaum graphite (sab xis) yog stacked los ntawm ntau txheej ntawm graphene los ntawm kev sib txuas ntawm van der Waals quab yuam.
Niaj hnub nim no, graphene tuaj yeem tau txais ntau txoj hauv kev, thiab ntau txoj kev muaj lawv tus kheej qhov zoo thiab qhov tsis zoo. Geim thiab Novoselov tau txais graphene hauv txoj kev yooj yim. Siv daim kab xev pob tshab muaj nyob rau hauv cov khw muag khoom loj, lawv tau rhuav tshem graphene, daim ntawv graphite nrog tsuas yog ib txheej ntawm cov pa roj carbon atoms tuab, los ntawm ib daim ntawm cov graphite pyrolytic siab. Qhov no yooj yim, tab sis kev tswj hwm tsis zoo, thiab graphene nrog qhov loj me tsawg dua 100 microns (ib feem kaum ntawm ib millimeter) tsuas yog tuaj yeem tau txais, uas tuaj yeem siv rau kev sim, tab sis nws nyuaj rau siv rau kev siv ua haujlwm. Kev tso pa tshuaj lom neeg tuaj yeem loj hlob cov qauv graphene nrog qhov loj me ntawm kaum centimeters ntawm qhov chaw hlau. Txawm hais tias thaj chaw nrog kev taw qhia sib xws tsuas yog 100 microns [3,4], nws tau tsim nyog rau kev xav tau ntau lawm ntawm qee qhov kev siv. Lwm txoj hauv kev siv ntau yog cua sov silicon carbide (SIC) siv lead ua kom ntau dua 1100 ℃ hauv lub tshuab nqus tsev, yog li cov silicon atoms ze ntawm qhov chaw evaporate, thiab cov pa roj carbon seem raug rov ua dua, uas kuj tuaj yeem tau txais cov qauv graphene nrog cov khoom zoo.
Graphene yog ib yam khoom tshiab uas muaj cov yam ntxwv tshwj xeeb: nws cov hluav taws xob conductivity zoo ib yam li tooj liab, thiab nws cov thermal conductivity zoo dua li lwm yam khoom siv paub. Nws pob tshab heev. Tsuas yog ib feem me me (2.3%) ntawm lub teeb pom kev ntsug yuav raug graphene nqus, thiab feem ntau ntawm lub teeb yuav hla dhau. Nws ntom heev uas txawm tias helium atoms (cov roj molecules me tshaj plaws) tsis tuaj yeem hla dhau. Cov yam ntxwv khawv koob no tsis yog los ntawm graphite, tab sis los ntawm quantum mechanics. Nws cov khoom hluav taws xob thiab kho qhov muag tshwj xeeb txiav txim siab tias nws muaj kev cia siab dav dav.
Txawm hais tias graphene tsuas yog tshwm sim tsawg dua kaum xyoo, nws tau qhia ntau yam kev siv tshuab, uas tsis tshua muaj nyob rau hauv cov teb ntawm physics thiab cov ntaub ntawv science. Nws siv sijhawm ntau dua kaum xyoo lossis txawm tias kaum xyoo rau cov ntaub ntawv dav dav kom txav mus los ntawm chav kuaj mus rau lub neej tiag tiag. Kev siv graphene yog dab tsi? Cia peb saib ob qho piv txwv.
Lub electrode mos mos pob tshab
Hauv ntau yam khoom siv hluav taws xob, cov khoom siv hluav taws xob uas muaj pob tshab yuav tsum tau siv ua cov electrodes. Cov moos hluav taws xob, cov tshuab xam zauv, cov TV, cov zaub siv lead ua kua, cov ntxaij vab tshaus kov, cov vaj huam sib luag hnub ci thiab ntau lwm yam khoom siv tsis tuaj yeem tawm ntawm cov electrodes pob tshab. Cov electrode pob tshab ib txwm siv indium tin oxide (ITO). Vim tias tus nqi siab thiab kev muab indium tsawg, cov khoom siv no tsis yooj yim thiab tsis muaj kev ywj pheej, thiab cov electrode yuav tsum tau tso rau hauv txheej nruab nrab ntawm lub tshuab nqus tsev, thiab tus nqi kuj siab heev. Tau ntev, cov kws tshawb fawb tau sim nrhiav nws cov khoom hloov. Ntxiv nrog rau qhov yuav tsum tau ua kom pob tshab, kev ua kom zoo thiab kev npaj yooj yim, yog tias qhov yooj yim ntawm cov khoom siv nws tus kheej zoo, nws yuav tsim nyog rau kev ua "ntawv hluav taws xob" lossis lwm yam khoom siv tso saib tau. Yog li ntawd, kev ywj pheej kuj yog ib qho tseem ceeb heev. Graphene yog cov khoom siv zoo li no, uas tsim nyog heev rau cov electrodes pob tshab.
Cov kws tshawb fawb los ntawm Samsung thiab Chengguan University hauv Kaus Lim Qab Teb tau txais graphene nrog qhov ntev ntawm 30 nti los ntawm kev tso pa tshuaj lom neeg thiab hloov mus rau 188 micron tuab polyethylene terephthalate (PET) zaj duab xis los tsim lub vijtsam kov graphene [4]. Raws li pom hauv daim duab hauv qab no, graphene loj hlob ntawm cov ntawv ci tooj liab yog thawj zaug sib txuas nrog daim kab xev thermal stripping (qhov xiav pob tshab), tom qab ntawd cov ntawv ci tooj liab yog yaj los ntawm txoj kev tshuaj lom neeg, thiab thaum kawg graphene raug hloov mus rau zaj duab xis PET los ntawm kev cua sov.
Cov khoom siv tshiab photoelectric induction
Graphene muaj cov khoom siv kho qhov muag tshwj xeeb heev. Txawm hais tias tsuas muaj ib txheej ntawm cov atoms, nws tuaj yeem nqus tau 2.3% ntawm lub teeb uas tawm hauv tag nrho cov wavelength ntawm lub teeb pom kev mus rau infrared. Tus lej no tsis muaj dab tsi ua rau lwm cov khoom siv ntawm graphene thiab yog txiav txim siab los ntawm quantum electrodynamics [6]. Lub teeb uas nqus tau yuav ua rau lub cim ntawm cov neeg nqa khoom (electrons thiab qhov). Lub cim thiab kev thauj mus los ntawm cov neeg nqa khoom hauv graphene txawv ntawm cov neeg hauv cov semiconductors ib txwm muaj. Qhov no ua rau graphene tsim nyog heev rau cov khoom siv ultrafast photoelectric induction. Nws kwv yees tias cov khoom siv photoelectric induction no yuav ua haujlwm ntawm qhov zaus ntawm 500ghz. Yog tias nws siv rau kev xa xov, nws tuaj yeem xa 500 billion xoom lossis ib qho ib ob, thiab ua tiav kev xa cov ntsiab lus ntawm ob lub Blu ray discs hauv ib ob.
Cov kws tshaj lij los ntawm IBM Thomas J. Watson Research Center hauv Tebchaws Meskas tau siv graphene los tsim cov khoom siv photoelectric induction uas tuaj yeem ua haujlwm ntawm 10GHz zaus [8]. Ua ntej, graphene flakes tau npaj rau ntawm silicon substrate them nrog 300 nm tuab silica los ntawm "tape tearing method", thiab tom qab ntawd palladium kub lossis titanium kub electrodes nrog lub sijhawm ntawm 1 micron thiab dav ntawm 250 nm tau ua rau nws. Ua li no, ib qho graphene raws li photoelectric induction device tau txais.
Daim duab kos ntawm cov khoom siv graphene photoelectric induction thiab scanning electron microscope (SEM) cov duab ntawm cov qauv tiag tiag. Cov kab luv luv dub hauv daim duab sib xws rau 5 microns, thiab qhov deb ntawm cov kab hlau yog ib micron.
Los ntawm kev sim, cov kws tshawb nrhiav pom tias cov hlau graphene hlau qauv photoelectric induction device no tuaj yeem ncav cuag qhov zaus ua haujlwm ntawm 16ghz ntawm qhov siab tshaj plaws, thiab tuaj yeem ua haujlwm ntawm qhov ceev ceev hauv qhov ntev ntawm 300 nm (ze ultraviolet) mus rau 6 microns (infrared), thaum lub raj photoelectric induction ib txwm tsis tuaj yeem teb rau lub teeb infrared nrog qhov ntev dua. Qhov zaus ua haujlwm ntawm graphene photoelectric induction khoom siv tseem muaj chaw zoo rau kev txhim kho. Nws qhov kev ua tau zoo tshaj plaws ua rau nws muaj ntau yam kev cia siab rau daim ntawv thov, suav nrog kev sib txuas lus, kev tswj chaw taws teeb thiab kev saib xyuas ib puag ncig.
Ua ib yam khoom tshiab uas muaj cov yam ntxwv tshwj xeeb, kev tshawb fawb txog kev siv graphene tab tom tshwm sim ib qho tom qab ib qho. Nws nyuaj rau peb suav lawv ntawm no. Yav tom ntej, tej zaum yuav muaj cov raj ua los ntawm graphene, cov hloov pauv molecular ua los ntawm graphene thiab cov khoom kuaj molecular ua los ntawm graphene hauv lub neej txhua hnub ... Graphene uas maj mam tawm hauv chav kuaj yuav ci ntsa iab hauv lub neej txhua hnub.
Peb tuaj yeem cia siab tias yuav muaj ntau yam khoom siv hluav taws xob uas siv graphene tshwm sim rau yav tom ntej. Xav txog seb nws yuav nthuav npaum li cas yog tias peb cov xov tooj ntse thiab netbooks tuaj yeem dov tau, clamped rau ntawm peb pob ntseg, ntim rau hauv peb lub hnab ris, lossis qhwv ib ncig ntawm peb lub dab teg thaum tsis siv!
Lub sijhawm tshaj tawm: Lub Peb Hlis-09-2022