Izinto ezinezici ezimbili, njenge-graphene, zikhanga kokubili izinhlelo zokusebenza ze-semiconductor ezivamile kanye nezinhlelo zokusebenza ezisafufusa kuma-electronics aguquguqukayo. Kodwa-ke, amandla aphezulu okuthambekela kwe-graphene aphumela ekuqhekekeni kokucindezeleka okuphansi, okwenza kube nzima ukusebenzisa izakhiwo zayo ezingavamile ze-elekthronikhi ezinwebekayo. Ukuze sikwazi ukusebenza kahle kakhulu kwama-conductor e-graphene acacile ancike ekucindezelweni, sakha ama-nanoscrolls e-graphene phakathi kwezingqimba ze-graphene ezihlanganisiwe, ezibizwa ngokuthi ama-multilayer graphene/graphene scrolls (MGGs). Ngaphansi kokucindezeleka, eminye imiqulu yahlanganisa izizinda ezihlukanisiwe ze-graphene ukuze kugcinwe inethiwekhi yokugoqa evumela ukuhanjiswa okuhle kakhulu kokucindezeleka okuphezulu. Ama-MGG e-Trilayer asekelwa kuma-elastomers agcine u-65% wokuhanjiswa kwawo kokuqala kokucindezeleka okungu-100%, okuqondene ngqo nesiqondiso sokugeleza kwamanje, kanti amafilimu e-trilayer e-graphene angenayo i-nanoscrolls agcine u-25% kuphela wokuhanjiswa kwawo kokuqala. I-transistor ye-all-carbon enwebekayo eyenziwe kusetshenziswa ama-MGG njengoba ama-electrode ebonise ukudluliselwa okungu->90% futhi agcina u-60% womkhiqizo wayo wamanje wokuqala ku-strain engu-120% (ngokuhambisana nesiqondiso sokuthutha kweshaja). Lawa ma-transistor e-all-carbon anwebekayo futhi asobala kakhulu angenza kube lula ama-optoelectronics anwebekayo ayinkimbinkimbi.
Ama-elekthronikhi acwebezelayo alula ayinsimu ekhulayo enezinhlelo ezibalulekile ezinhlelweni ezithuthukisiwe ze-biointegrated (1, 2) kanye nekhono lokuhlanganiswa nama-optoelectronics alula (3, 4) ukukhiqiza amarobhothi athambile ayinkimbinkimbi kanye nezibonisi. I-Graphene ikhombisa izakhiwo ezifiselekayo kakhulu zobukhulu be-athomu, ukubonakala okuphezulu, kanye nokuqhuba okuphezulu, kodwa ukusetshenziswa kwayo ekusetshenzisweni okulula kuye kwavinjelwa ukuthambekela kwayo kokuqhekeka emigqeni emincane. Ukunqoba imikhawulo yemishini ye-graphene kungenza kube lula ukusebenza okusha kumadivayisi acwebezelayo alula.
Izakhiwo eziyingqayizivele ze-graphene ziyenza ibe yi-candidate eqinile yesizukulwane esilandelayo sama-electrode okuhambisa abonakalayo (5, 6). Uma kuqhathaniswa ne-transparent conductor esetshenziswa kakhulu, i-indium tin oxide [ITO; 100 ohms/square (sq) ku-90% transparency ], i-monolayer graphene ekhuliswa yi-chemical vapor deposition (CVD) inenhlanganisela efanayo yokumelana neshidi (125 ohms/sq) kanye nokubonakala (97.4%) (5). Ngaphezu kwalokho, amafilimu e-graphene anokuguquguquka okungavamile uma kuqhathaniswa ne-ITO (7). Isibonelo, ku-substrate yepulasitiki, ukuhamba kwayo kungagcinwa ngisho naserediyasi egobile yokugoba encane njenge-0.8 mm (8). Ukuze kuthuthukiswe ukusebenza kwayo kagesi njengomqhubi oguquguqukayo obonakalayo, imisebenzi yangaphambilini ithuthukise izinto ze-graphene hybrid ezinezintambo zesiliva ezine-dimensional (1D) eyodwa noma ama-carbon nanotubes (CNTs) (9–11). Ngaphezu kwalokho, i-graphene isetshenziswe njengama-electrode kuma-semiconductors ahlanganisiwe ane-dimensional heterostructural (njenge-2D bulk Si, i-1D nanowires/nanotubes, kanye nama-0D quantum dots) (12), ama-transistors aguquguqukayo, amaseli elanga, kanye nama-diode akhipha ukukhanya (ama-LED) (13–23).
Nakuba i-graphene ibonise imiphumela ethembisayo yama-electronics aguquguqukayo, ukusetshenziswa kwayo kuma-electronics anwebekayo kuye kwanqunywa yizakhiwo zayo zemishini (17, 24, 25); i-graphene inokuqina okungaphakathi kwendiza okungu-340 N/m kanye ne-modulus kaYoung engu-0.5 TPa (26). Inethiwekhi enamandla ye-carbon-carbon ayinikezi noma yiziphi izindlela zokuhlakazeka kwamandla okucindezela okusetshenzisiwe ngakho-ke iyaqhekeka kalula ngaphansi kokucindezeleka okungaphansi kuka-5%. Isibonelo, i-CVD graphene edluliselwe kwi-polydimethylsiloxane (PDMS) elastic substrate ingagcina kuphela ukuhanjiswa kwayo ngaphansi kokucindezeleka okungaphansi kuka-6% (8). Izibalo zethiyori zibonisa ukuthi ukuqhekeka nokuxhumana phakathi kwezingqimba ezahlukene kufanele kunciphise kakhulu ukuqina (26). Ngokufaka i-graphene ezingqimbeni eziningi, kubikwa ukuthi le graphene ye-bi- noma ye-trilayer inwebeka ibe yi-30% yokucindezela, ikhombisa ushintsho lokumelana oluncane ngokuphindwe ka-13 kuneye-monolayer graphene (27). Kodwa-ke, lokhu kwelulwa kusengaphansi kakhulu kune-c onductors ezinwebekayo zesimanje (28, 29).
Ama-transistors abalulekile ekusetshenzisweni okunwebekayo ngoba avumela ukufundwa kwezinzwa okuyinkimbinkimbi kanye nokuhlaziywa kwesignali (30, 31). Ama-transistors ku-PDMS ane-graphene enezingqimba eziningi njengama-electrode omthombo/okukhipha kanye nezinto zesiteshi angagcina ukusebenza kukagesi kufikela ku-5% yobunzima (32), okungaphansi kakhulu kwenani eliphansi elidingekayo (~50%) lama-sensors okuqapha impilo agqokwayo kanye nesikhumba se-elekthronikhi (33, 34). Muva nje, indlela ye-graphene kirigami ihlolisisiwe, futhi i-transistor evalwe yi-electrolyte ewuketshezi inganwetshwa ifike ku-240% (35). Kodwa-ke, le ndlela idinga i-graphene emisiwe, okwenza inqubo yokukhiqiza ibe nzima.
Lapha, sifinyelela amadivayisi e-graphene anwebeka kakhulu ngokuhlanganisa imiqulu ye-graphene (~1 kuya ku-20 μm ubude, ~0.1 kuya ku-1 μm ububanzi, kanye ~10 kuya ku-100 nm ukuphakama) phakathi kwezingqimba ze-graphene. Sicabanga ukuthi le miqulu ye-graphene inganikeza izindlela zokuhambisa ugesi ukuze kuvalwe imifantu kumashidi e-graphene, ngaleyo ndlela igcine ugesi ophezulu ngaphansi kokucindezeleka. Imiqulu ye-graphene ayidingi ukwenziwa noma inqubo eyengeziwe; yakhiwa ngokwemvelo ngesikhathi senqubo yokudlulisa amanzi. Ngokusebenzisa imiqulu ye-graphene ye-G/G (graphene/graphene) (MGGs) yama-electrode anwebekayo (umthombo/ukudonsa kanye nesango) kanye nama-CNT acubungulayo, sikwazile ukubonisa ama-transistors e-all-carbon asobala kakhulu futhi anwebeka kakhulu, anganwebeka abe yi-strain engu-120% (ngokuhambisana nesiqondiso sokuthutha kweshaja) futhi agcine u-60% womkhiqizo wawo wamanje wokuqala. Lena yi-transistor esekelwe ku-carbon esobala kakhulu enwebeka kakhulu kuze kube manje, futhi inikeza ugesi owanele ukushayela i-LED engaphili.
Ukuze sivumele ama-electrode e-graphene anwebekayo abonakalayo endaweni enkulu, sikhethe i-graphene ekhuliswe nge-CVD ku-Cu foil. I-Cu foil yalengiswa phakathi neshubhu ye-CVD quartz ukuvumela ukukhula kwe-graphene kuzo zombili izinhlangothi, kwakha izakhiwo ze-G/Cu/G. Ukuze sidlulisele i-graphene, saqala samboza ungqimba oluncane lwe-poly(methyl methacrylate) (PMMA) ukuze sivikele uhlangothi olulodwa lwe-graphene, esasiqamba ngokuthi i-topside graphene (ngokuphambene nalokho kolunye uhlangothi lwe-graphene), futhi kamuva, lonke ifilimu (PMMA/top graphene/Cu/bottom graphene) lacwiliswa kusisombululo se-(NH4)2S2O8 ukuze kukhishwe i-Cu foil. I-graphene eseceleni engezansi ngaphandle kwe-PMMA coating ngokuqinisekile izoba nemifantu kanye namaphutha avumela i-etchant ukuthi ingene (36, 37). Njengoba kuboniswe ku-Fig. 1A, ngaphansi komthelela wokucindezeleka kobuso, izindawo ze-graphene ezikhishwe zagoqwa zaba imiqulu futhi kamuva zanamathiselwa kufilimu esele ye-top-G/PMMA. Imiqulu ephezulu ye-G/G ingadluliselwa kunoma iyiphi i-substrate, njenge-SiO2/Si, ingilazi, noma i-polymer ethambile. Ukuphinda le nqubo yokudlulisa izikhathi eziningana kwi-substrate efanayo kunikeza izakhiwo ze-MGG.
(A) Umfanekiso wesimiso wenqubo yokwenziwa kwama-MGG njenge-electrode elula. Ngesikhathi sokudluliselwa kwe-graphene, i-graphene yangemuva ku-Cu foil yaphulwa emingceleni naseziphazameni, yagoqwa yaba yizimo ezingahleliwe, yabe isinamathiselwa ngokuqinile kumafilimu aphezulu, yakha ama-nanoscrolls. Ikhathuni yesine ibonisa isakhiwo se-MGG esihlanganisiwe. (B no-C) Ukucaciswa kwe-TEM okuphezulu kwe-MGG ye-monolayer, okugxile esifundeni se-monolayer graphene (B) kanye nesifunda se-scroll (C), ngokulandelana. I-inset ye-(B) isithombe esiphansi esibonisa isimo se-monolayer MGGs kugridi ye-TEM. Ama-insets e-(C) amaphrofayili okuqina athathwe emabhokisini angunxande aboniswe esithombeni, lapho amabanga phakathi kwezindiza ze-athomu angama-0.34 kanye no-0.41 nm. (D) I-Carbon K-edge EEL spectrum enezimpawu ze-graphitic π* kanye ne-σ* peaks ezibhalwe. (E) Isithombe se-Sectional AFM se-monolayer G/G scrolls esinephrofayili yokuphakama eceleni komugqa ophuzi onamachashazi. (F kuya ku-I) I-optical microscopy kanye nesithombe se-AFM se-trilayer G ngaphandle kwe-(F no-H) kanye ne-scrolls (G no-I) kuma-substrate e-SiO2/Si angu-300-nm-thick, ngokulandelana. Ama-scrolls amele kanye nemibimbi kwafakwa ilebula ukuze kugqanyiswe umehluko wawo.
Ukuze siqinisekise ukuthi imiqulu iyi-graphene egoqiwe ngokwemvelo, senze izifundo ze-spectroscopy ye-electron microscopy (TEM) kanye ne-electron energy loss (EEL) ezinhlakeni ze-monolayer top-G/G scroll. Isithombe 1B sibonisa isakhiwo esinama-hexagonal se-graphene ye-monolayer, futhi ingxenye engezansi iyisimo sefilimu esimbozwe emgodini owodwa wekhabhoni wegridi ye-TEM. I-graphene ye-monolayer ihlanganisa iningi legridi, futhi amanye ama-flakes e-graphene lapho kukhona izinqwaba eziningi zamasongo ane-hexagonal avela (Isithombe 1B). Ngokusondeza ku-scroll ngayinye (Isithombe 1C), sibone inani elikhulu lama-lattice fringes e-graphene, kanye nesikhala se-lattice esisukela ku-0.34 kuya ku-0.41 nm. Lezi zilinganiso zisikisela ukuthi ama-flakes agoqiwe ngokungahleliwe futhi awawona ama-graphite aphelele, anesikhala se-lattice esingu-0.34 nm ekubekweni kwengqimba "ye-ABAB". Isithombe 1D sibonisa i-carbon K-edge EEL spectrum, lapho ukuphakama ku-285 eV kuvela ku-π* orbital kanti okunye okuzungeze i-290 eV kungenxa yokuguquka kwe-σ* orbital. Kungabonakala ukuthi ukubopha kwe-sp2 kuyabusa kulesi sakhiwo, okuqinisekisa ukuthi imiqulu inemifanekiso eminingi.
Izithombe ze-optical microscopy kanye ne-atomic force microscopy (AFM) zinikeza ukuqonda ngokusatshalaliswa kwe-graphene nanoscrolls kuma-MGG (Isithombe 1, E kuya ku-G, kanye nama-fig. S1 kanye no-S2). Imiqulu isatshalaliswa ngokungahleliwe phezu kobuso, futhi ubuningi bayo ngaphakathi kwendiza buyanda ngokulinganayo nenani lezingqimba ezihlanganisiwe. Imiqulu eminingi ihlanganiswe ibe amafindo futhi ibonisa ukuphakama okungalingani ebangeni eliphakathi kuka-10 kuya ku-100 nm. Inobude obuyi-1 kuya ku-20 μm kanye nobubanzi obuyi-0.1 kuya ku-1 μm, kuye ngobukhulu bezingqimba zayo zokuqala ze-graphene. Njengoba kuboniswe ku-Isithombe 1 (H kanye no-I), imiqulu inobukhulu obukhulu kakhulu kunemibimbi, okuholela ekuhlanganeni okuqinile phakathi kwezingqimba ze-graphene.
Ukuze silinganise izakhiwo zikagesi, senze amaphethini amafilimu e-graphene anezakhiwo zokuskrola noma angenazo kanye nokuqoqwa kwezingqimba zibe yimigqa engu-300-μm ububanzi kanye nengu-2000-μm ubude sisebenzisa i-photolithography. Ukumelana kwe-two-probe njengomsebenzi wokucindezeleka kwalinganiswa ngaphansi kwezimo ze-ambient. Ukuba khona kwe-scrolls kunciphisa ukumelana kwe-monolayer graphene ngo-80% ngokuncipha okungu-2.2% kuphela kokudluliselwa (umfanekiso S4). Lokhu kuqinisekisa ukuthi ama-nanoscrolls, anomthamo wamanje ophezulu ofinyelela ku-5 × 107 A/cm2 (38, 39), enza umnikelo omuhle kakhulu kagesi kuma-MGG. Phakathi kwawo wonke ama-mono-, bi-, kanye nama-trilayer plain graphene kanye nama-MGG, i-trilayer MGG inomoya omuhle kakhulu onokucaca okucishe kube ngu-90%. Ukuze siqhathanise neminye imithombo ye-graphene ebikwe ezincwadini, silinganise nokumelana kweshidi okune-probe ezine (umfanekiso S5) futhi sikubhale njengomsebenzi wokudlulisa ku-550 nm (umfanekiso S6) ku-Fig. 2A. I-MGG ikhombisa ukuqhutshwa komoya okufana noma okuphezulu kanye nokucaca kune-graphene ehlanganisiwe enezingqimba eziningi kanye ne-graphene oxide encishisiwe (RGO) (6, 8, 18). Qaphela ukuthi ukumelana kweshidi kwe-graphene ehlanganisiwe enezingqimba eziningi ezivela ezincwadini kuphakeme kancane kunokwe-MGG yethu, mhlawumbe ngenxa yezimo zayo zokukhula ezingalungiswanga kanye nendlela yokudlulisa.
(A) Ukumelana kweshidi okune-probe okune-four probe uma kuqhathaniswa nokudluliselwa ku-550 nm kwezinhlobo eziningana ze-graphene, lapho izikwele ezimnyama zimelela i-MGGs ye-mono-, bi-, kanye ne-trilayer; imibuthano ebomvu kanye nonxantathu oluhlaza okwesibhakabhaka kufana ne-graphene engenalutho enezingqimba eziningi ekhuliswe ku-Cu kanye ne-Ni kusukela ezifundweni zikaLi et al. (6) kanye noKim et al. (8), ngokulandelana, futhi kamuva idluliselwe ku-SiO2/Si noma i-quartz; futhi onxantathu abaluhlaza bangamanani e-RGO ngamadigri ahlukene okunciphisa kusukela ocwaningweni lukaBonaccorso et al. (18). (B kanye no-C) Ukushintsha kokumelana okujwayelekile kwe-MGGs ye-mono-, bi- kanye ne-trilayer kanye ne-G njengomsebenzi wokucindezeleka okuqondile (B) kanye nokuhambisana (C) kuya esiqondisweni sokugeleza kwamanje. (D) Ukushintsha kokumelana okujwayelekile kwe-bilayer G (obomvu) kanye ne-MGG (omnyama) ngaphansi kokulayisha kokucindezeleka okujikelezayo okufika ku-50% kokucindezeleka okuqondile. (E) Ukushintsha kokumelana okujwayelekile kwe-trilayer G (obomvu) kanye ne-MGG (omnyama) ngaphansi kokulayisha kokucindezeleka okujikelezayo okufika ku-90%. (F) Ushintsho olujwayelekile lwe-capacitance lwe-mono-, bi- kanye ne-trilayer G kanye ne-bi- kanye ne-trilayer MGGs njengomsebenzi wokucindezeleka. I-insert isakhiwo se-capacitor, lapho i-polymer substrate iyi-SEBS kanti ungqimba lwe-polymer dielectric luyi-2-μm-thick SEBS.
Ukuze sihlole ukusebenza kwe-MGG okuncike ekucindezelweni, sidlulisele i-graphene kuma-substrate e-thermoplastic elastomer styrene-ethylene-butadiene-styrene (SEBS) (~2 cm ububanzi kanye nobude obungu-5 cm), futhi ukuhanjiswa kwamandla kwalinganiswa njengoba i-substrate yeluliwe (bheka Izinto Nezindlela) kokubili ngokuqondene futhi kuhambisane nesiqondiso sokugeleza kwamanje (Isithombe 2, B kanye no-C). Ukuziphatha kukagesi okuncike ekucindezelweni kwathuthuka ngokufakwa kwama-nanoscrolls kanye nenani elikhulayo lezingqimba ze-graphene. Isibonelo, lapho ukucindezeleka kuqondene nokugeleza kwamanje, kwi-monolayer graphene, ukungezwa kwemiqulu kwandisa ukucindezeleka lapho kuphuka ugesi kusuka ku-5 kuya ku-70%. Ukubekezelelana kokucindezeleka kwe-trilayer graphene nakho kuthuthuke kakhulu uma kuqhathaniswa ne-monolayer graphene. Ngama-nanoscrolls, ku-100% perpendicular strain, ukumelana kwesakhiwo se-trilayer MGG kukhuphuke ngo-50% kuphela, uma kuqhathaniswa no-300% we-trilayer graphene ngaphandle kwemiqulu. Ushintsho lokumelana ngaphansi komthwalo wokucindezeleka ojikelezayo luhlolisisiwe. Ukuze kuqhathaniswe (Isithombe 2D), ukumelana kwefilimu ye-bilayer graphene ecacile kwanda cishe izikhathi ezingu-7.5 ngemva kwemijikelezo engu-~700 ngokucindezeleka okungu-50% okuqondile futhi kwaqhubeka nokukhula ngokucindezeleka emjikelezweni ngamunye. Ngakolunye uhlangothi, ukumelana kwe-bilayer MGG kwanda cishe izikhathi ezingu-2.5 ngemva kwemijikelezo engu-~700. Ngokusebenzisa ubunzima obufika ku-90% ohlangothini oluhambisanayo, ukumelana kwe-trilayer graphene kwanda ~ izikhathi ezingu-100 ngemva kwemijikelezo engu-1000, kuyilapho kungama-~8 kuphela ku-trilayer MGG (Isithombe 2E). Imiphumela yokujikeleza iboniswe ku-Fig. S7. Ukwanda okusheshayo kokumelana ohlangothini oluhambisanayo kungenxa yokuthi ukuqondiswa kwemifantu kuqondile ohlangothini lokugeleza kwamanje. Ukuphambuka kokumelana ngesikhathi sokulayisha nokulayisha umthwalo kungenxa yokubuyiselwa kwe-viscoelastic kwe-SEBS elastomer substrate. Ukumelana okuzinzile kwemigqa ye-MGG ngesikhathi sokuhamba ngebhayisikili kungenxa yokuba khona kwemiqulu emikhulu engavimba izingxenye eziqhekekile ze-graphene (njengoba kubonwe yi-AFM), okusiza ukugcina indlela egobhozayo. Lesi simo sokugcina ukuguquguquka kwendlela egobhozayo sike sabikwa ngaphambili kumafilimu ensimbi noma e-semiconductor aqhekekile kuma-substrate e-elastomer (40, 41).
Ukuze sihlole la mafilimu asekelwe ku-graphene njengama-electrode esango kumadivayisi anwebekayo, simboze ungqimba lwe-graphene ngengqimba ye-dielectric ye-SEBS (ubukhulu obungu-2 μm) futhi saqapha ushintsho lwe-capacitance ye-dielectric njengomsebenzi wokucindezeleka (bheka i-Fig. 2F kanye nezinto ezengeziwe ukuze uthole imininingwane). Sibone ukuthi ama-capacitance anama-electrode e-graphene e-monolayer acacile kanye ne-bilayer ancipha ngokushesha ngenxa yokulahlekelwa yi-conductivity ye-graphene engaphakathi. Ngokuphambene nalokho, ama-capacitance avikelwe yi-MGGs kanye ne-graphene e-trilayer ecacile abonise ukwanda kwe-capacitance ngokucindezeleka, okulindeleke ngenxa yokwehla kobukhulu be-dielectric ngokucindezeleka. Ukwanda okulindelekile kwe-capacitance kufanelane kahle kakhulu nesakhiwo se-MGG (isithombe S8). Lokhu kubonisa ukuthi i-MGG ifaneleka njenge-electrode yesango yama-transistors anwebekayo.
Ukuze siqhubeke siphenye indima ye-1D graphene scroll ekubekezeleleni kokucindezeleka kokuqhuba kukagesi nokulawula kangcono ukuhlukaniswa phakathi kwezingqimba ze-graphene, sisebenzise ama-CNT afakwe i-spray ukuze sithathe indawo ye-graphene scrolls (bheka Izinto Ezingeziwe). Ukuze silingise izakhiwo ze-MGG, sifake ubuningi obuthathu be-CNTs (okungukuthi, i-CNT1).
(Kusukela ku-A kuya ku-C) Izithombe ze-AFM zobuningi obuhlukene obuthathu be-CNTs (CNT1)
Ukuze siqonde kabanzi ikhono labo njengama-electrode e-elekthronikhi anwebekayo, sihlole ngokuhlelekile izimo ze-MGG kanye ne-G-CNT-G ngaphansi kokucindezeleka. I-optical microscopy kanye ne-scanning electron microscopy (SEM) akuzona izindlela ezisebenzayo zokuchaza ngoba zombili azinawo umehluko wombala futhi i-SEM ingaphansi kwezithombe zobuciko ngesikhathi sokuskena ama-electron lapho i-graphene ikuma-polymer substrates (izithombe S9 kanye ne-S10). Ukuze sibone ubuso be-graphene ngaphansi kokucindezeleka endaweni, siqoqe izilinganiso ze-AFM kuma-trilayer MGG kanye ne-plain graphene ngemva kokudlulisela kuma-substrates amancane kakhulu (~0.1 mm ubukhulu) kanye nama-elastic SEBS. Ngenxa yeziphambeko zangaphakathi ku-CVD graphene kanye nomonakalo wangaphandle ngesikhathi senqubo yokudlulisa, imifantu ikhiqizwa ngokungenakugwenywa ku-graphene ecindezelwe, futhi ngokucindezeleka okwandayo, imifantu yaba miningi (Isithombe 4, A kuya ku-D). Kuye ngesakhiwo sokufaka ama-electrode asekelwe ku-carbon, imifantu ibonisa izimo ezahlukene (Isithombe S11) (27). Ubuningi bendawo yokuqhekeka (echazwa njengendawo yokuqhekeka/indawo ehlaziyiwe) ye-graphene enezingqimba eziningi bungaphansi kobe-graphene enezingqimba ezimbili ngemva kokucindezeleka, okuhambisana nokwanda kokuqhuba kukagesi kwe-MGGs. Ngakolunye uhlangothi, imiqulu ivame ukubonwa ukuze ivale imiqulu, inikeze izindlela ezengeziwe zokuqhuba kufilimu ecindezelwe. Isibonelo, njengoba kubhalwe esithombeni se-Fig. 4B, umqulu obanzi uwele phezu komqulu ku-MGG enezingqimba ezintathu, kodwa akukho mqulu obonwe ku-graphene ecacile (Isithombe 4, E kuya ku-H). Ngokufanayo, ama-CNT nawo avale imiqulu ku-graphene (isithombe S11). Ubuningi bendawo yokuqhekeka, ubuningi bendawo yokuskrola, kanye nobunzima bamafilimu kufingqiwe ku-Fig. 4K.
(A kuya ku-H) Izithombe ze-AFM ezitholakala endaweni ye-trilayer G/G scrolls (A kuya ku-D) kanye nezakhiwo ze-trilayer G (E kuya ku-H) ku-elastomer encane kakhulu ye-SEBS (~0.1 mm ubukhulu) ku-strain engu-0, 20, 60, kanye no-100%. Imifantu emele kanye nemifantu ikhonjwe ngemicibisholo. Zonke izithombe ze-AFM zisendaweni engu-15 μm × 15 μm, kusetshenziswa ibha yesikali sombala ofanayo njengoba ilebula. (I) I-geometry yokulingisa yama-electrode e-graphene e-monolayer anephethini ku-substrate ye-SEBS. (J) Imephu ye-contour yokulingisa yohlobo oluphezulu lwe-logarithmic ku-graphene ye-monolayer kanye ne-substrate ye-SEBS ku-strain yangaphandle engu-20%. (K) Ukuqhathaniswa kobuningi bendawo yokuqhekeka (ikholomu ebomvu), ubuningi bendawo yokuskrola (ikholomu ephuzi), kanye nobukhali bendawo (ikholomu eluhlaza okwesibhakabhaka) yezakhiwo ezahlukene ze-graphene.
Uma amafilimu e-MGG enwetshiwe, kunendlela ebalulekile eyengeziwe yokuthi imiqulu ingakwazi ukuvala izindawo eziqhekekile ze-graphene, igcine inethiwekhi egoqayo. Imiqulu ye-graphene iyathembisa ngoba ingaba amashumi ama-micrometer ubude futhi ngaleyo ndlela ikwazi ukuvala imiqulu evame ukufika esikalini se-micrometer. Ngaphezu kwalokho, ngenxa yokuthi imiqulu iqukethe izingqimba eziningi ze-graphene, kulindeleke ukuthi ibe nokumelana okuphansi. Uma kuqhathaniswa, amanethiwekhi e-CNT aminyene (aphansi okudlulisa) ayadingeka ukuze anikeze ikhono elifanayo lokuvala imiqulu, njengoba ama-CNT amancane (ngokuvamile ama-micrometer ambalwa ubude) futhi angaphansi kokuhambisa imiqulu. Ngakolunye uhlangothi, njengoba kuboniswe ku-fig. S12, kuyilapho i-graphene iqhekeka ngesikhathi sokwelula ukuze ivumelane nokucindezeleka, imiqulu ayiqhekeki, okubonisa ukuthi lokhu kwamuva kungenzeka ukuthi kuyashelela ku-graphene engaphansi. Isizathu sokuthi aziqhekeki kungenzeka ukuthi sibangelwa isakhiwo esigoqiwe, esakhiwe yizingqimba eziningi ze-graphene (~1 kuya ku-2 0 μm ubude, ~0.1 kuya ku-1 μm ububanzi, kanye ~10 kuya ku-100 nm ukuphakama), ene-modulus esebenza kahle kakhulu kune-graphene enezingqimba eyodwa. Njengoba kubikwe nguGreen noHersam (42), amanethiwekhi e-metallic CNT (ububanzi beshubhu engu-1.0 nm) angafinyelela ukumelana okuphansi kweshidi <100 ohms/sq naphezu kokumelana okukhulu kwe-junction phakathi kwe-CNTs. Uma sibheka ukuthi i-graphene scrolls yethu inobubanzi obungu-0.1 kuya ku-1 μm nokuthi i-G/G scrolls inezindawo zokuxhumana ezinkulu kakhulu kune-CNTs, ukumelana kokuxhumana nendawo yokuxhumana phakathi kwe-graphene ne-graphene scrolls akufanele kube yizinto ezivimbela ukugcina ukuhanjiswa okuphezulu.
I-graphene ine-modulus ephezulu kakhulu kune-substrate ye-SEBS. Nakuba ubukhulu obusebenzayo be-electrode ye-graphene buphansi kakhulu kunobe-substrate, ukuqina kwe-graphene kuphindaphinda ubukhulu bayo kufana nokwe-substrate (43, 44), okuholela kumphumela oqinile wesiqhingi olinganiselayo. Silingise ukuguquguquka kwe-graphene engu-1-nm-thick ku-substrate ye-SEBS (bheka Izinto Ezingeziwe ukuze uthole imininingwane). Ngokusho kwemiphumela yokulingisa, lapho kufakwa i-strain engu-20% ku-substrate ye-SEBS ngaphandle, i-strain ejwayelekile ku-graphene ingu-~6.6% (Isithombe 4J kanye nomfanekiso S13D), okuhambisana nokubonwa kokuhlola (bheka umfanekiso S13). Siqhathanise i-strain ezifundeni ze-graphene ezinephethini kanye ne-substrate sisebenzisa i-optical microscopy futhi sathola ukuthi i-strain esifundeni se-substrate okungenani iphindwe kabili kune-strain esifundeni se-graphene. Lokhu kubonisa ukuthi i-strain esetshenziswa kumaphethini e-electrode ye-graphene ingavinjelwa kakhulu, yakha iziqhingi eziqinile ze-graphene phezu kwe-SEBS (26, 43, 44).
Ngakho-ke, ikhono lama-electrode e-MGG lokugcina ukuhanjiswa okuphezulu ngaphansi kokucindezeleka okuphezulu cishe livunyelwe izindlela ezimbili ezinkulu: (i) Imiqulu ingahlanganisa izifunda ezingaxhunyiwe ukuze igcine indlela yokudonsa eqhubayo, kanye (ii) amashidi/i-elastomer ye-graphene enezingqimba eziningi ingashelela phezu komunye nomunye, okuholela ekunciphiseni ukucindezeleka kuma-electrode e-graphene. Ezingqimbeni eziningi ze-graphene edluliselwe ku-elastomer, izingqimba azinamathelene ngokuqinile, ezingashelela ngenxa yokucindezeleka (27). Imiqulu iphinde yandisa ubulukhuni bezingqimba ze-graphene, okungasiza ukwandisa ukuhlukaniswa phakathi kwezingqimba ze-graphene futhi ngaleyo ndlela kuvumele ukushelela kwezingqimba ze-graphene.
Amadivayisi e-carbon yonke alandelwa ngentshiseko ngenxa yezindleko eziphansi kanye nomthamo ophezulu. Esimweni sethu, ama-transistors e-carbon yonke akhiwe kusetshenziswa isango le-graphene elingezansi, umthombo we-graphene ongaphezulu/ukuxhumana kokukhipha, i-semiconductor ye-CNT ehleliwe, kanye ne-SEBS njenge-dielectric (Isithombe 5A). Njengoba kuboniswe ku-Isithombe 5B, idivayisi ye-carbon yonke ene-CNTs njengomthombo/ukukhipha kanye nesango (idivayisi engezansi) ayibonakali kakhulu kunedivayisi ene-graphene electrodes (idivayisi ephezulu). Lokhu kungenxa yokuthi amanethiwekhi e-CNT adinga ukuqina okukhulu, futhi ngenxa yalokho, ukudluliselwa okubonakalayo okuphansi ukuze kufezwe ukumelana kweshidi okufana nokwe-graphene (Isithombe S4). Isibalo 5 (C no-D) sibonisa ama-curve okudlulisela kanye nokuphuma okumele ngaphambi kokucindezeleka kwe-transistor eyenziwe ngama-electrode e-MGG angenawo ungqimba. Ububanzi besiteshi kanye nobude be-transistor engacindezelwanga kwakungu-800 no-100 μm, ngokulandelana. Isilinganiso sokuvala/sokuvala esilinganisiwe sikhulu kuno-103 ngama-current okuvula nokucisha emazingeni angu-10−5 no-10−8 A, ngokulandelana. Ijika lokukhipha libonisa izindlela ezifanele zokuqondisa eziqondile kanye nezingaguquguquki ngokuxhomekeka okucacile kwesango-voltage, okubonisa ukuxhumana okufanele phakathi kwama-CNT nama-electrode e-graphene (45). Ukumelana kokuxhumana nama-electrode e-graphene kubonwe kuphansi kunalokho okunefilimu ye-Au ephefumulayo (bheka isithombe S14). Ukuhamba kokugcwala kwe-transistor enwebekayo cishe kungama-5.6 cm2/Vs, okufana nokwama-transistor e-CNT ahlelwe nge-polymer kuma-substrate e-Si aqinile ane-300-nm SiO2 njengesendlalelo se-dielectric. Ukuthuthukiswa okwengeziwe kokuhamba kungenzeka ngobuningi be-tube obulungiselelwe kanye nezinye izinhlobo zama-tube (46).
(A) Uhlelo lwe-transistor enwebekayo esekelwe ku-graphene. Ama-SWNT, ama-carbon nanotubes anodonga olulodwa. (B) Isithombe sama-transistor enwebekayo enziwe ngama-electrode e-graphene (phezulu) nama-electrode e-CNT (ngezansi). Umehluko ekukhanyeni ubonakala ngokucacile. (C no-D) Ama-curve okudlulisa nokukhipha we-transistor esekelwe ku-graphene ku-SEBS ngaphambi kokucindezeleka. (E no-F) Ama-curve okudlulisa, ukuvala nokuvala ugesi, isilinganiso sokuvala/sokuvala, kanye nokuhamba kwe-transistor esekelwe ku-graphene ezinhlotsheni ezahlukene.
Lapho idivayisi ecacile, enekhabhoni yonke inwetshwa ngendlela ehambisana nesiqondiso sokuthutha ishaja, ukuwohloka okuncane kwabonakala kuze kufike ku-120% yokucindezeleka. Ngesikhathi sokwelula, ukuhamba kwehla ngokuqhubekayo kusuka ku-5.6 cm2/Vs ku-0% yokucindezeleka kuya ku-2.5 cm2/Vs ku-120% yokucindezeleka (Isithombe 5F). Siphinde saqhathanisa ukusebenza kwe-transistor ngobude obuhlukene besiteshi (bheka ithebula S1). Okuphawulekayo ukuthi, ku-strain enkulu njenge-105%, wonke lawa ma-transistor asabonisa isilinganiso esiphezulu sokuvula/ukuvala ( >103) kanye nokuhamba ( >3 cm2/Vs). Ngaphezu kwalokho, sifingqe wonke umsebenzi wakamuva kuma-transistor ekhabhoni yonke (bheka ithebula S2) (47–52). Ngokwenza ngcono ukwenziwa kwedivayisi kuma-elastomers nokusebenzisa ama-MGG njengoxhumana nabo, ama-transistor ethu ekhabhoni yonke abonisa ukusebenza okuhle ngokuya ngokuhamba kanye ne-hysteresis kanye nokuba lula kakhulu ukwelula.
Njengokusetshenziswa kwe-transistor ecacile ngokuphelele futhi enwebekayo, siyisebenzise ukulawula ukushintsha kwe-LED (Isithombe 6A). Njengoba kuboniswe ku-Fig. 6B, i-LED eluhlaza ingabonakala ngokucacile ngedivayisi ye-all-carbon enwebekayo ebekwe ngqo ngenhla. Ngenkathi inwebeka ku-~100% (Isithombe 6, C no-D), ukuqina kokukhanya kwe-LED akushintshi, okuhambisana nokusebenza kwe-transistor okuchazwe ngenhla (bheka i-movie S1). Lona umbiko wokuqala wamayunithi okulawula anwebekayo enziwe kusetshenziswa ama-electrode e-graphene, okubonisa ithuba elisha lama-electronics anwebekayo e-graphene.
(A) Isekethe ye-transistor yokushayela i-LED. I-GND, phansi. (B) Isithombe se-transistor ye-all-carbon enwebekayo nebonakalayo ku-0% strain efakwe ngaphezu kwe-LED eluhlaza. (C) I-transistor ekhanyayo neyonwebekayo esetshenziswa ukushintsha i-LED ifakwe ngaphezu kwe-LED ku-0% (kwesobunxele) kanye no-~100% strain (kwesokudla). Imicibisholo emhlophe ikhomba njengezimpawu eziphuzi kudivayisi ukukhombisa ushintsho lwebanga olunwebekayo. (D) Umbono ohlangothini lwe-transistor enwebekayo, i-LED icindezelwe ku-elastomer.
Ekuphetheni, sithuthukise isakhiwo se-graphene esibonakalayo esigcina ukuhanjiswa okuphezulu ngaphansi kwezinhlobo ezinkulu njengama-electrode anwebekayo, anikwe amandla yi-graphene nanoscrolls phakathi kwezingqimba ze-graphene ezihlanganisiwe. Lezi zakhiwo ze-electrode ze-MGG ze-bi- kanye ne-trilayer MGG ku-elastomer zingagcina u-21 no-65%, ngokulandelana, we-0% strain conductivity yazo ekucindezelweni okuphezulu njengo-100%, uma kuqhathaniswa nokulahlekelwa okuphelele kokuhanjiswa komoya ku-5% strain yama-electrode e-graphene ajwayelekile e-monolayer. Izindlela ezengeziwe zokuhambisa umoya ze-graphene scrolls kanye nokusebenzisana okubuthakathaka phakathi kwezingqimba ezidluliselwe kunikela ekuzinzeni kokuhambisa umoya okuphezulu ngaphansi kokucindezeleka. Siphinde sasebenzisa lesi sakhiwo se-graphene ukwakha ama-transistors anwebekayo e-all-carbon. Kuze kube manje, lena yi-transistor esekelwe ku-graphene enwebekayo kakhulu enokucaca okungcono kakhulu ngaphandle kokusebenzisa i-buckling. Nakuba lolu cwaningo lwenziwe ukuze kuvunyelwe i-graphene kuma-electronics anwebekayo, sikholelwa ukuthi le ndlela inganwetshwa kwezinye izinto ze-2D ukuze kuvunyelwe ama-electronics e-2D anwebekayo.
I-graphene ye-CVD yendawo enkulu ikhuliswe kuma-foil e-Cu alengisiwe (99.999%; i-Alfa Aesar) ngaphansi kokucindezela okungaguquki okungu-0.5 mtorr nge-50–SCCM (isentimitha elijwayelekile le-cubic ngomzuzu) i-CH4 kanye ne-20–SCCM H2 njengezibikezelo ku-1000°C. Zombili izinhlangothi ze-foil ye-Cu zazimbozwe yi-monolayer graphene. Ingqimba encane ye-PMMA (2000 rpm; A4, Microchem) yambozwa ngopende ohlangothini olulodwa lwe-foil ye-Cu, yakha isakhiwo se-PMMA/G/Cu foil/G. Ngemva kwalokho, lonke ifilimu lacwiliswa kusisombululo se-0.1 M ammonium persulfate [(NH4)2S2O8] cishe amahora ama-2 ukuze kukhishwe i-foil ye-Cu. Phakathi nale nqubo, i-graphene engavikelekile yangemuva yaqala yadabula imingcele yezinhlamvu yabe isigoqwa yaba imiqulu ngenxa yokucindezeleka kobuso. Imiqulu yanamathiselwa kwifilimu ye-graphene ephezulu esekelwa yi-PMMA, yakha imiqulu ye-PMMA/G/G. Ngemva kwalokho amafilimu ahlanzwa ngamanzi acwengekile izikhathi eziningana futhi abekwa endaweni ehlosiwe, njenge-SiO2/Si eqinile noma i-substrate yepulasitiki. Lapho nje ifilimu enamathiselwe yoma endaweni engezansi, isampula yacwiliswa ngokulandelana ku-acetone, i-1:1 acetone/IPA (isopropyl alcohol), kanye ne-IPA imizuzwana engama-30 ngayinye ukuze kususwe i-PMMA. Amafilimu ashiswa ku-100°C imizuzu eyi-15 noma agcinwe endaweni evalekile ubusuku bonke ukuze kususwe ngokuphelele amanzi avalelekile ngaphambi kokuba kudluliselwe enye ingqimba ye-G/G scroll kuyo. Lesi sinyathelo kwakuwukugwema ukuhlukaniswa kwefilimu ye-graphene kusuka endaweni engezansi nokuqinisekisa ukumbozwa okugcwele kwama-MGG ngesikhathi sokukhululwa kwengqimba ye-PMMA carrier.
Ukwakheka kwesakhiwo se-MGG kwabonwa kusetshenziswa i-optical microscope (Leica) kanye ne-scanning electron microscope (1 kV; FEI). I-atomic force microscope (Nanoscope III, Digital Instrument) yasetshenziswa kwimodi yokuthepha ukuze kubonwe imininingwane ye-G scrolls. Ukucaca kwefilimu kwahlolwa nge-ultraviolet-visible spectrometer (Agilent Cary 6000i). Ezivivinyweni lapho uhlobo lwaluseceleni kokuqondisa kokugeleza kwamanje, i-photolithography kanye ne-O2 plasma kwasetshenziswa ukupeyinta izakhiwo ze-graphene zibe yimichilo (~300 μm ububanzi kanye no-~2000 μm ubude), kanye nama-electrode e-Au (50 nm) afakwa ngokushisa kusetshenziswa izithunzi zobuso kuzo zombili izinhlangothi zohlangothi olude. Ama-graphene strips abe esefakwa ku-SEBS elastomer (~2 cm ububanzi kanye nobude obungu-~5 cm), lapho i-axis ende yama-strips ihambisana nohlangothi olufushane lwe-SEBS ilandelwa yi-BOE (buffered oxide etch) (HF:H2O 1:6) etching kanye ne-eutectic gallium indium (EGaIn) njengokuxhumana kukagesi. Ekuhlolweni kokucindezeleka okuhambisanayo, izakhiwo ze-graphene ezingafakwanga iphethini (~5 × 10 mm) zadluliselwa kuma-substrate e-SEBS, kanye nama-axes amade ahambisana nohlangothi olude lwe-substrate ye-SEBS. Kuzo zombili izimo, yonke i-G (ngaphandle kwe-G scrolls)/SEBS yeluliwe ohlangothini olude lwe-elastomer ku-appliance manual, futhi endaweni, silinganise izinguquko zokumelana kwazo ngaphansi kokucindezeleka esiteshini se-probe nge-semiconductor analyzer (Keithley 4200-SCS).
Ama-transistor e-all-carbon anwebeka kakhulu futhi abonakala kalula ku-substrate enwebekayo enziwe ngezinqubo ezilandelayo ukugwema umonakalo we-organic solvent we-polymer dielectric kanye ne-substrate. Izakhiwo ze-MGG zadluliselwa ku-SEBS njengama-electrode esango. Ukuze kutholakale ungqimba lwe-polymer dielectric olufana nolwe-thin-film (2 μm ubukhulu), isixazululo se-SEBS toluene (80 mg/ml) safakwa nge-spin-coating ku-octadecyltrichlorosilane (OTS)–modified SiO2/Si substrate ku-1000 rpm umzuzu owodwa. Ifilimu ye-dielectric encane ingadluliselwa kalula kusuka ebusweni be-hydrophobic OTS iye ku-substrate ye-SEBS embozwe yi-graphene elungiselelwe. I-capacitor ingenziwa ngokufaka i-electrode ephezulu ye-liquid-metal (EGaIn; Sigma-Aldrich) ukuze kutholakale i-capacitance njengomsebenzi wokucindezeleka kusetshenziswa imitha ye-LCR (inductance, capacitance, resistance) (Agilent). Enye ingxenye ye-transistor yayiqukethe ama-semiconducting CNT ahlelwe nge-polymer, kulandela izinqubo ezibikwe ngaphambilini (53). Ama-electrod omthombo/okukhipha amaphethini enziwe kuma-substrate e-SiO2/Si aqinile. Ngemva kwalokho, izingxenye ezimbili, i-dielectric/G/SEBS kanye ne-CNTs/i-G/SiO2/Si ephethini, zahlanganiswa, zacwiliswa ku-BOE ukuze kususwe i-substrate e-SiO2/Si eqinile. Ngakho-ke, ama-transistors acacile futhi anwebekayo akhiwe. Ukuhlolwa kukagesi ngaphansi kokucindezeleka kwenziwa ngokusethwa kokwelula ngesandla njengendlela eshiwo ngenhla.
Izinto ezengeziwe zalesi sihloko ziyatholakala ku-http://advances.sciencemag.org/cgi/content/full/3/9/e1700159/DC1
umfanekiso S1. Izithombe ze-optical microscopy ze-monolayer MGG kuma-substrate e-SiO2/Si ekukhulisweni okuhlukene.
umfanekiso S4. Ukuqhathaniswa kokumelana kweshidi le-probe ezimbili kanye nokudluliselwa okungu-550 nm kwe-mono-, bi- kanye ne-trilayer plain graphene (izikwele ezimnyama), i-MGG (izindilinga ezibomvu), kanye nama-CNT (unxantathu oluhlaza okwesibhakabhaka).
isithombe S7. Ushintsho olujwayelekile lokumelana kwama-MGG e-mono- kanye ne-bilayer (amnyama) kanye no-G (obomvu) ngaphansi kobunzima obuyi-~1000 obuhamba ngomjikelezo obulayisha kufika ku-40 kanye no-90% wobunzima obuhambisanayo, ngokulandelana.
umfanekiso S10. Isithombe se-SEM se-trilayer MGG ku-elastomer ye-SEBS ngemva kokucindezeleka, sibonisa ukugoqa okude okuwela phezu kwemifantu eminingana.
umfanekiso S12. Isithombe se-AFM se-trilayer MGG ku-elastomer encane kakhulu ye-SEBS ku-strain engu-20%, okubonisa ukuthi umqulu uwele phezu komfantu.
ithebula S1. Ukunyakaza kwama-transistors e-bilayer MGG–single-walled carbon nanotube ngobude obuhlukene besiteshi ngaphambi nangemva kokucindezeleka.
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QAPHELA: Sicela ikheli lakho le-imeyili kuphela ukuze umuntu oncoma ikhasi azi ukuthi ubufuna alibone, nokuthi akulona iposi elingafuneki. Asithathi noma yiliphi ikheli le-imeyili.
Lo mbuzo ungowokuhlola ukuthi ungumuntu ovakashile noma cha nokuvimbela ukuthunyelwa kogaxekile okuzenzakalelayo.
NguNan Liu, Alex Chortos, Ting Lei, Lihua Jin, Taeho Roy Kim, Won-Gyu Bae, Chenxin Zhu, Sihong Wang, Raphael Pfattner, Xiyuan Chen, Robert Sinclair, Zhenan Bao
NguNan Liu, Alex Chortos, Ting Lei, Lihua Jin, Taeho Roy Kim, Won-Gyu Bae, Chenxin Zhu, Sihong Wang, Raphael Pfattner, Xiyuan Chen, Robert Sinclair, Zhenan Bao
© 2021 Inhlangano YaseMelika Yokuthuthukiswa Kwesayensi. Wonke Amalungelo Agodliwe. I-AAAS inguzakwethu we-HINARI, AGORA, OARE, CHORUS, CLOCKSS, CrossRef kanye ne-COUNTER.Science Advances ISSN 2375-2548.
Isikhathi sokuthunyelwe: Jan-28-2021