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ʻO nā kiʻi ʻoniʻoni graphite nanoscale (NGFs) he mau nanomaterial ikaika i hiki ke hana ʻia e ka hoʻoheheʻe ʻana i ka mahu kemika catalytic, akā mau nā nīnau e pili ana i ko lākou maʻalahi o ka hoʻololi ʻana a pehea ka hopena o ka morphology o ka honua i kā lākou hoʻohana ʻana i nā hāmeʻa e hiki mai ana. Maʻaneʻi mākou e hōʻike i ka uluʻana o NGF ma nāʻaoʻaoʻelua o kahi polycrystalline nickel foil (kahi 55 cm2, mānoanoa e pili ana i 100 nm) a me kona polymer-free transfer (mua a me hope, kahi a hiki i 6 cm2). Ma muli o ka morphology o ka catalyst foil, ʻokoʻa nā kiʻi kalapona ʻelua i ko lākou mau waiwai kino a me nā ʻano ʻē aʻe (e like me ka ʻili o ka ʻili). Hōʻike mākou i nā NGF me kahi ʻaoʻao ʻoi aku ka maikaʻi no ka ʻike NO2, ʻoiai nā NGF maʻalahi a ʻoi aku ka conductive ma ka ʻaoʻao mua (2000 S / cm, pale pale - 50 ohms / m2) hiki ke lilo i mau alakaʻi kūpono. kaila a i ʻole electrode o ka cell solar (no ka mea, hoʻouna ʻo ia i 62% o ka mālamalama ʻike). Ma ke ʻano holoʻokoʻa, hiki ke kōkua i ka hoʻomohala ʻana a me ka lawe ʻana i ka NGF ma ke ʻano he mea kalapona ʻē aʻe no nā noi ʻenehana kahi i kūpono ʻole nā kiʻi graphene a me ka micron-thick graphite.
ʻO ka graphite kahi mea ʻenehana i hoʻohana nui ʻia. ʻO ka mea nui, loaʻa i ka graphite nā waiwai o ka haʻahaʻa haʻahaʻa haʻahaʻa a me ke kiʻekiʻe o ka mokulele i ka wela a me ka conductivity uila, a paʻa loa i nā kaiapuni wela a me nā kemika1,2. ʻO Flake graphite kahi mea hoʻomaka kaulana no ka noiʻi graphene3. Ke hana ʻia i loko o nā kiʻi ʻoniʻoni lahilahi, hiki ke hoʻohana ʻia i ka nui o nā noi, e komo pū ana me ka wela wela no nā mea uila e like me smartphones4,5,6,7, ma ke ʻano he mea ikaika i nā sensors8,9,10 a no ka pale ʻana i ka electromagnetic interference11. 12 a me nā kiʻiʻoniʻoni no ka lithography i ka ultraviolet loa13,14, e alakaʻi ana i nā ala i loko o nā cell solar15,16. No kēia mau noi āpau, he mea maikaʻi loa ia inā hiki ke hana a lawe ʻia nā wahi nui o nā kiʻi graphite (NGF) me nā mānoanoa i hoʻomalu ʻia i ka nanoscale <100 nm.
Hana ʻia nā kiʻi ʻoniʻoni graphite e nā ʻano hana like ʻole. I kekahi hihia, ua hoʻohana ʻia ka hoʻopili ʻana a me ka hoʻonui ʻia e ka exfoliation e hana i nā flakes graphene10,11,17. Pono e hana hou ʻia nā flakes i mau kiʻiʻoniʻoni o ka mānoanoa i makemake ʻia, a he mau lā ia e hana ai i nā pepa graphite paʻa. ʻO kekahi ala ʻē aʻe e hoʻomaka me nā precursor paʻa graphitable. Ma ka ʻoihana, ua kalapona ʻia nā ʻāpana polymers (ma 1000–1500 °C) a laila kiʻi ʻia (ma 2800–3200 °C) e hana i nā mea i hoʻonohonoho pono ʻia. ʻOiai he kiʻekiʻe ka maikaʻi o kēia mau kiʻiʻoniʻoni, he mea nui ka hoʻohana ʻana i ka ikehu1,18,19 a ʻo ka liʻiliʻi o ka mānoanoa i kaupalena ʻia i kekahi mau microns1,18,19,20.
ʻO Catalytic chemical vapor deposition (CVD) kahi ala kaulana no ka hana ʻana i nā kiʻi ʻoniʻoni graphene a me ultrathin graphite (<10 nm) me ke kūlana kiʻekiʻe a me ke kumu kūʻai kūpono21,22,23,24,25,26,27. Eia nō naʻe, ke hoʻohālikelike ʻia me ka ulu ʻana o ka graphene a me nā kiʻi ʻoniʻoni ultrathin graphite28, ʻoi aku ka liʻiliʻi o ka ulu ʻana o ka nui a me / a i ʻole ka noi ʻana o NGF e hoʻohana ana i CVD11,13,29,30,31,32,33.
Pono e hoʻoili pinepine ʻia nā kiʻi ʻoniʻoni kiʻi kiʻi kiʻi kiʻi kiʻi CVD a me nā kiʻi ʻoniʻoni kiʻi ma luna o nā substrates hana34. ʻO kēia mau hoʻoili kiʻiʻoniʻoni lahilahi e pili ana i ʻelua mau ʻano kumu nui35: (1) hoʻoili non-etch36,37 a me (2) hoʻoili kemika mākū etch-based (kākoʻo ʻia ka substrate)14,34,38. Loaʻa i kēlā me kēia ala kekahi mau pono a me nā hemahema a pono e koho ʻia ma muli o ka noi i manaʻo ʻia, e like me ka wehewehe ʻana ma kahi ʻē aʻe35,39. No nā kiʻi ʻoniʻoni graphene/graphite i ulu ʻia ma nā substrates catalytic, hoʻololi ʻia ma o nā kaʻina hana kemika pulu (ʻo ia ka polymethyl methacrylate (PMMA) ka papa kākoʻo maʻamau i hoʻohana ʻia) ʻo ia ke koho mua13,30,34,38,40,41,42. ʻO ʻoe et al. Ua'ōleloʻiaʻaʻole i hoʻohanaʻia ka polymer no ka hoʻololi NGF (ka nui o ka laʻana ma kahi o 4 cm2) 25,43, akā,ʻaʻole i hāʻawiʻia nā kiko'ī e pili ana i ka paʻa a me ka lawelaweʻana i ka wā o ka hoʻoiliʻana; ʻO nā kaʻina hana wet chemistry e hoʻohana ana i nā polymers he mau ʻanuʻu, me ka noi ʻana a me ka wehe ʻana o kahi papa polymer mōhai30,38,40,41,42. Loaʻa nā hemahema o kēia kaʻina hana: no ka laʻana, hiki i nā koena polymer ke hoʻololi i nā waiwai o ke kiʻiʻoniʻoni ulu38. Hiki i ka hana hou ke hoʻoneʻe i ke koena polymer, akā ʻo kēia mau hana hou e hoʻonui i ke kumukūʻai a me ka manawa o ka hana kiʻiʻoniʻoni38,40. I ka ulu ʻana o CVD, waiho ʻia kahi papa graphene ʻaʻole wale ma ka ʻaoʻao mua o ka pahu catalyst (ka ʻaoʻao e kū pono ana i ka kahe mahu), akā ma kona ʻaoʻao hope. Eia nō naʻe, ua manaʻo ʻia ka mea hope he huahana ʻōpala a hiki ke wehe koke ʻia e ka plasma palupalu38,41. Hiki i ka hana hou ʻana i kēia kiʻiʻoniʻoni ke kōkua i ka hoʻonui ʻana i ka hua, ʻoiai inā ʻoi aku ka maikaʻi ma mua o ke kiʻi carbon carbon.
Maʻaneʻi, hōʻike mākou i ka hoʻomākaukau ʻana i ka ulu bifacial wafer-scale o NGF me ke kūlana kiʻekiʻe ma ka polycrystalline nickel foil e CVD. Ua ʻike ʻia pehea ka pili ʻana o ka ʻala o ka mua a me ka ʻili hope o ka foil i ka morphology a me ke ʻano o NGF. Hōʻike pū mākou i ka hoʻololi ʻana o ka polymer-free NGF i nā kumu kūʻai maikaʻi a me ke kaiapuni mai nā ʻaoʻao ʻelua o ka nickel foil ma luna o nā substrate multifunctional a hōʻike i ke kūpono o nā kiʻiʻoniʻoni mua a me hope no nā noi like ʻole.
Kūkākūkā nā ʻāpana ma lalo nei i nā mānoanoa kiʻi ʻoniʻoni like ʻole e pili ana i ka helu o nā papa graphene i hoʻopaʻa ʻia: (i) papa kiʻi kiʻi hoʻokahi (SLG, 1 papa), (ii) liʻiliʻi papa graphene (FLG, <10 papa), (iii) graphene multilayer ( MLG, 10-30 papa) a me (iv) NGF (~300 papa). ʻO ka hope ka mānoanoa maʻamau i hōʻike ʻia ma ke ʻano he pākēneka o ka ʻāpana (ma kahi o 97% ʻāpana no 100 µm2)30. ʻO ia ke kumu i kapa ʻia ai ke kiʻi holoʻokoʻa he NGF.
ʻO nā pepa nickel polycrystalline i hoʻohana ʻia no ka synthesis o nā kiʻi graphene a me nā kiʻi graphite he mau ʻano like ʻole ma muli o kā lākou hana ʻana a me ka hana ʻana ma hope. Ua hōʻike koke mākou i kahi noiʻi e hoʻonui i ke kaʻina ulu o NGF30. Hōʻike mākou i nā ʻāpana kaʻina hana e like me ka manawa annealing a me ke kaomi o ke keʻena i ka wā o ka ulu ʻana he hana koʻikoʻi i ka loaʻa ʻana o nā NGF o ka mānoanoa like ʻole. Maʻaneʻi, ua noiʻi hou mākou i ka uluʻana o NGF ma mua o ka poli i hoʻomaʻemaʻeʻia (FS) a me ke kuaʻole (BS) o ka nickel foil (Fig. 1a). ʻEkolu ʻano o nā laʻana FS a me BS i nānā ʻia, i helu ʻia ma ka Papa 1. Ma ka nānā ʻana, hiki ke ʻike ʻia ka ulu like ʻana o NGF ma nā ʻaoʻao ʻelua o ka nickel foil (NiAG) e ka hoʻololi ʻana o ka waihoʻoluʻu o ka nui Ni substrate mai kahi kālā metala. hina i ke kala hina hina (Fig. 1a); ua hōʻoia ʻia nā ana microscopic (Fig. 1b, c). Hōʻike ʻia kahi kikoʻī Raman maʻamau o FS-NGF ma ka ʻāpana ʻālohilohi a hōʻike ʻia e nā pua ʻulaʻula, uliuli a ʻalani ma ke Kiʻi 1b ma ke Kiʻi 1c. ʻO nā hiʻohiʻona Raman peaks o graphite G (1683 cm−1) a me 2D (2696 cm−1) e hōʻoia i ka ulu ʻana o ka NGF crystalline kiʻekiʻe (Fig. 1c, Table SI1). I loko o ke kiʻiʻoniʻoni, ua ʻike ʻia kahi predominance o Raman spectra me ka ratio intensity (I2D/IG) ~0.3, ʻoiai ʻo Raman spectra me I2D/IG = 0.8 ʻaʻole i ʻike ʻia. ʻO ka loaʻaʻole o nā piko hemahema (D = 1350 cm-1) ma ke kiʻi holoʻokoʻa e hōʻike ana i ke kiʻekiʻe o ka uluʻana o NGF. Loaʻa nā hopena Raman like ma ka laʻana BS-NGF (Figure SI1 a me b, Table SI1).
Hoʻohālikelike o NiAG FS- a me BS-NGF: (a) Paʻi kiʻi o kahi laʻana NGF (NiAG) maʻamau e hōʻike ana i ka ulu ʻana o NGF ma ka pālākiō wafer (55 cm2) a me nā mea hoʻohālike BS- a me FS-Ni foil, (b) FS-NGF Nā kiʻi/ Ni i loaʻa ma ka microscope opi, (c) ʻano ʻano Raman spectra i hoʻopaʻa ʻia ma nā kūlana like ʻole ma ka panel b, (d, f) nā kiʻi SEM ma nā hoʻonui like ʻole ma FS-NGF/Ni, (e, g) nā kiʻi SEM ma nā hoʻonui like ʻole. Hoʻonohonoho BS -NGF/Ni. Hōʻike ka pua polū i ka ʻāina FLG, hōʻike ka pua ʻalani i ka ʻāina MLG (kokoke i ka ʻāina FLG), hōʻike ka pua ʻulaʻula i ka ʻāpana NGF, a ʻo ka pua magenta e hōʻike i ka pa.
No ka mea e pili ana ka ulu ʻana i ka mānoanoa o ka substrate mua, ka nui aniani, ka hoʻonohonoho ʻana, a me nā palena palaoa, ʻo ka loaʻa ʻana o ka mana kūpono o ka mānoanoa NGF ma luna o nā wahi nui he paʻakikī20,34,44. Ua hoʻohana kēia haʻawina i nā ʻike a mākou i paʻi mua ai 30. Hoʻopuka kēia kaʻina hana i kahi ʻāpana mālamalama o 0.1 a 3% no 100 µm230. Ma nā ʻāpana aʻe, hōʻike mākou i nā hopena no nā ʻano ʻāpana ʻelua. Hōʻike nā kiʻi SEM hoʻonui kiʻekiʻe i ka hiki ʻana o kekahi mau wahi ʻokoʻa ʻālohilohi ma nā ʻaoʻao ʻelua (Fig. 1f,g), e hōʻike ana i ka hiki ʻana mai o nā wahi FLG a me MLG30,45. Ua hōʻoia pū ʻia kēia e ka hoʻopuehu ʻana o Raman (Fig. 1c) a me nā hopena TEM (i kūkākūkā ʻia ma hope ma ka ʻāpana "FS-NGF: hale a me nā waiwai"). ʻO nā ʻāpana FLG a me MLG i ʻike ʻia ma nā laʻana FS- a me BS-NGF/Ni (mua a me hope NGF i ulu ma Ni) ua ulu paha ma luna o nā hua nui Ni (111) i hana ʻia i ka wā pre-annealing22,30,45. Ua ʻike ʻia ka pelu ʻana ma nā ʻaoʻao ʻelua (Fig. 1b, i kaha ʻia me nā pua poni). Loaʻa pinepine kēia mau paʻi i nā kiʻi graphene a me nā kiʻi graphite CVD ma muli o ka ʻokoʻa nui o ka coefficient o ka hoʻonui wela ma waena o ka graphite a me ka nickel substrate30,38.
Ua hōʻoia ke kiʻi AFM ua ʻoi aku ka palahalaha o ka laʻana FS-NGF ma mua o ka hōʻailona BS-NGF (Figure SI1) (Figure SI2). ʻO nā kumu kumu kumu huinahā (RMS) koʻikoʻi koʻikoʻi o FS-NGF/Ni (Fig. SI2c) a me BS-NGF/Ni (Fig. SI2d) he 82 a me 200 nm, kēlā me kēia (ana ʻia ma kahi ʻāpana o 20 × 20 μm2). Hiki ke ho'omaopopo 'ia ka 'o'ole'a ki'eki'e ma muli o ka 'ilikai ili o ka nickel (NiAR) foil ma ka moku'āina i loa'a (Figure SI3). Hōʻike ʻia nā kiʻi SEM o FS a me BS-NiAR ma nā Kiʻi SI3a–d, e hōʻike ana i nā ʻano morphologies o ka ʻili: i hoʻoliʻi ʻia ʻo FS-Ni foil he nano a me ka micron-spherical particles, ʻoiai unpolished BS-Ni foil hōʻike i kahi alapiʻi hana. e like me nā ʻāpana me ka ikaika kiʻekiʻe. a emi iho. Hōʻike ʻia nā kiʻi hoʻonā haʻahaʻa a kiʻekiʻe o ka nickel foil annealed (NiA) ma ke Kiʻi SI3e–h. Ma kēia mau huahelu, hiki iā mākou ke nānā i ka loaʻa ʻana o kekahi mau ʻāpana nickel nui micron ma nā ʻaoʻao ʻelua o ka nickel foil (Fig. SI3e–h). Loaʻa paha i nā kīʻaha nui ka Ni(111) i ka ʻili, e like me ka mea i hōʻike mua ʻia30,46. Aia nā ʻokoʻa nui i ka morphology nickel foil ma waena o FS-NiA a me BS-NiA. ʻO ke kiʻekiʻe o ka roughness o BS-NGF/Ni ma muli o ka ʻili ʻole o ka BS-NiAR, ʻo ka ʻili o ia mea e mau ana ka ʻeleʻele ma hope o ka hoʻopili ʻana (Figure SI3). ʻO kēia ʻano ʻano o ka ʻili ma mua o ka ulu ʻana o ka ulu ʻana e hiki ai ke hoʻomalu ʻia ke ʻano o ka graphene a me nā kiʻi graphite. Pono e hoʻomaopopo ʻia ua hoʻoponopono hou ʻia ka ʻōpala kumu i ka wā o ka ulu ʻana o ka graphene, kahi i hoʻemi iki i ka nui o ka palaoa a hoʻonui iki i ka ʻili o ka lepo i hoʻohālikelike ʻia me ka foil annealed a me ka kiʻi catalyst22.
ʻO ka hoʻomaʻamaʻa maikaʻi ʻana i ka ʻili o ka substrate, ka manawa annealing (ka nui o ka palaoa) 30,47 a me ka hoʻokuʻu ʻana i ka control43 e kōkua i ka hōʻemi ʻana i ka mānoanoa NGF kūloko i ka µm2 a/a i ʻole nm2 pālākiō (ʻo ia hoʻi, nā ʻano mānoanoa o kekahi mau nanometer). No ka hoʻomalu ʻana i ka ʻeleʻele o ka substrate, hiki ke noʻonoʻo ʻia nā ʻano e like me ka electrolytic polishing o ka nickel foil hopena. A laila hiki ke hoʻopili ʻia ka nickel foil i hoʻomaʻamaʻa ʻia ma kahi haʻahaʻa haʻahaʻa (<900 °C) 46 a me ka manawa (<5 min) e pale ai i ka hoʻokumu ʻana o nā hua nui Ni(111) (he mea pono no ka ulu ʻana o FLG).
ʻAʻole hiki iā SLG a me FLG graphene ke kū i ka ʻili o ka ʻili o nā waikawa a me ka wai, e koi ana i nā papa kākoʻo mechanical i ka wā o nā kaʻina hoʻololi kemika pulu22,34,38. Ma ka hoʻokaʻawale ʻana i ka hoʻoili ʻana o ka graphene38 i kākoʻo ʻia i ka polymer, ua ʻike mākou e hiki ke hoʻololi ʻia nā ʻaoʻao ʻelua o ka NGF i ulu ʻole me ke kākoʻo polymer, e like me ka mea i hōʻike ʻia ma ke Kiʻi 2a (e nānā i ke Kiʻi SI4a no nā kikoʻī hou aku). Hoʻomaka ka hoʻololi ʻana o NGF i kahi substrate i hāʻawi ʻia me ka etching pulu o ke kiʻi Ni30.49 lalo. Hoʻokomo ʻia nā mea hoʻohālike NGF / Ni / NGF i ka pō ma 15 mL o 70% HNO3 i hoʻoheheʻe ʻia me 600 mL o ka wai deionized (DI). Ma hope o ka hoʻoheheʻe ʻia ʻana o ka Ni foil, e noho palahalaha ana ka FS-NGF a lana ma ka ili o ka wai, e like me ka laana NGF/Ni/NGF, oiai ua hookomoia o BS-NGF i ka wai (Fig. 2a,b). A laila ua hoʻoneʻe ʻia ka NGF i hoʻokaʻawale ʻia mai kekahi beaker i loaʻa ka wai deionized hou i kekahi beaker a ua holoi maikaʻi ʻia ka NGF i hoʻokaʻawale ʻia, e hana hou ana i ʻehā a ʻeono manawa ma o ka ipu aniani concave. ʻO ka hope, ua kau ʻia ʻo FS-NGF a me BS-NGF ma luna o ka substrate i makemake ʻia (Fig. 2c).
ʻO ke kaʻina hoʻololi kemika pulu polimer-ʻole no NGF i ulu ʻia ma luna o ka nickel foil: (a) Kaʻina hana kahe (e nānā i ke Kiʻi SI4 no nā kikoʻī hou aku), (b) Kiʻi kiʻi kiʻi o NGF i hoʻokaʻawale ʻia ma hope o Ni etching (2 laʻana), (c) Laʻana FS - a me ka BS-NGF e hoʻololi i ka SiO2/Si substrate, (d) FS-NGF e hoʻololi i ka opaque polymer substrate, (e) BS-NGF mai ka laʻana like me ka panel d (māhele ʻia i ʻelua ʻāpana), hoʻololi ʻia i ka pepa C i uhi ʻia i ke gula. a me Nafion (ka mea hoʻoheheʻe maʻalahi, nā kihi i kaha ʻia me nā kihi ʻulaʻula).
E hoʻomaopopo i ka hoʻololi ʻana o SLG me ka hoʻohana ʻana i nā ʻano hoʻololi kemika pulu e pono ai ka manawa hana holoʻokoʻa o 20-24 hola 38 . Me ka ʻenehana hoʻoili polymer-free i hōʻike ʻia ma ʻaneʻi (Figure SI4a), ua hoʻemi nui ʻia ka manawa hana hoʻoili NGF holoʻokoʻa (ma kahi o 15 mau hola). ʻO ke kaʻina hana: (Step 1) E hoʻomākaukau i kahi hopena etching a kau i ka hāpana i loko (~ 10 mau minuke), a laila kali i ka pō no Ni etching (~ 7200 minuke), (Step 2) Holoi me ka wai deionized (Step - 3) . E mālama i loko o ka wai deionized a i ʻole e hoʻoneʻe i ka substrate target (20 min). Hoʻopau ʻia ka wai i hoʻopaʻa ʻia ma waena o ka NGF a me ka matrix nui e ka hana capillary (me ka hoʻohana ʻana i ka pepa blotting)38, a laila hoʻoneʻe ʻia nā kulu wai i koe e ka maloʻo maoli (ma kahi o 30 min), a ma hope o ka hoʻomaloʻo ʻana i ka hāpana no 10 min. min i loko o ka umu (10–1 mbar) ma 50–90 °C (60 min) 38.
ʻIke ʻia ʻo Graphite e kū i ke alo o ka wai a me ka ea ma nā wela kiʻekiʻe (≥ 200 °C)50,51,52. Ua hoʻāʻo mākou i nā laʻana me ka hoʻohana ʻana i Raman spectroscopy, SEM, a me XRD ma hope o ka waiho ʻana i loko o ka wai deionized i ka lumi wela a i loko o nā hue i hoʻopaʻa ʻia no nā wahi a pau mai kekahi mau lā a i hoʻokahi makahiki (Figure SI4). ʻAʻole ʻike ʻia ka degradation. Hōʻike ka Figure 2c i ka FS-NGF a me BS-NGF i ka wai deionized. Ua hopu mākou iā lākou ma kahi substrate SiO2 (300 nm) / Si, e like me ka mea i hōʻike ʻia ma ka hoʻomaka o ka Figure 2c. Eia hou, e like me ka mea i hōʻike ʻia ma ka Figure 2d,e, hiki ke hoʻololi ʻia ka NGF mau i nā substrate like ʻole e like me nā polymers (Thermabright polyamide mai Nexolve a me Nafion) a me ka pepa kalapona i uhi ʻia i ke gula. Hoʻokomo maʻalahi ka FS-NGF e lana ana ma luna o ka substrate target (Fig. 2c, d). Eia nō naʻe, paʻakikī ke mālama ʻana i nā laʻana BS-NGF i ʻoi aku ka nui ma mua o 3 cm2 i ka wā i hoʻokomo ʻia i loko o ka wai. ʻO ka mea maʻamau, ke hoʻomaka lākou e ʻōwili i loko o ka wai, ma muli o ka mālama pono ʻole ʻana i kekahi manawa, nahaha lākou i ʻelua a ʻekolu paha ʻāpana (Fig. 2e). Ma keʻano holoʻokoʻa, ua hiki iā mākou ke hoʻokō i ka hoʻoili polymer-free o PS- a me BS-NGF (hoʻololi mau ʻole me ka ulu ʻole o NGF / Ni / NGF ma 6 cm2) no nā laʻana a hiki i ka 6 a me 3 cm2 ma kahi. Hiki ke ʻike ʻia nā ʻāpana nui a liʻiliʻi paha i koe (maʻalahi i ka etching solution a i ʻole ka wai deionized) ma ka substrate i makemake ʻia (~ 1 mm2, Kiʻi SI4b, e ʻike i ka hāpana i hoʻololi ʻia i ka pā keleawe e like me "FS-NGF: Structure and Properties (kūkākūkā ʻia) ma lalo o “Structure and Properties”) a i ʻole hale kūʻai no ka hoʻohana e hiki mai ana (Figure SI4). Ma muli o kēia criterion, manaʻo mākou e hiki ke hoʻihoʻi ʻia ka NGF i nā hua a hiki i 98-99% (ma hope o ka ulu ʻana no ka hoʻololi).
Hoʻokaʻawale ʻia nā laʻana me ka polymer ʻole. ʻO nā hiʻohiʻona morphological i loaʻa ma FS- a me BS-NGF / SiO2 / Si (Fig. 2c) me ka hoʻohana ʻana i ka microscopy optical (OM) a me nā kiʻi SEM (Fig. SI5 a me Fig. 3) ua hōʻike ʻia ua hoʻoili ʻia kēia mau laʻana me ka ʻole o ka microscopy. ʻIke ʻia ka pōʻino kino e like me nā māwae, nā lua, a i ʻole nā wahi i wehe ʻia. ʻO nā paʻi ma luna o ka NGF e ulu ana (Fig. 3b, d, i kaha ʻia e nā pua poni) i noho paʻa ma hope o ka hoʻoili ʻana. ʻO nā FS- a me BS-NGF nā ʻāpana FLG (nā ʻāpana ʻālohilohi i hōʻike ʻia e nā pua polū ma ke Kiʻi 3). ʻO ka mea kupanaha, ʻaʻole like me nā wahi i hōʻino ʻia i ʻike pinepine ʻia i ka wā o ka hoʻololi ʻana o ka polymer o nā kiʻi ʻoniʻoni ultrathin graphite, ua hoʻoili ʻia kekahi mau micron-sized FLG a me MLG wahi e pili ana i ka NGF (i hōʻailona ʻia e nā pua polū ma ke Kiʻi 3d) i hoʻoili ʻia me ka ʻole o nā māwae a me nā haki (Figure 3d) . 3). . Ua hoʻokūpaʻa hou ʻia ka pono mechanical me ka hoʻohana ʻana i nā kiʻi TEM a me SEM o NGF i hoʻoili ʻia ma luna o ka lace-carbon copper grids, e like me ka mea i kūkākūkā ʻia ma hope ("FS-NGF: Structure and Properties"). ʻOi aku ka paʻakikī o ka BS-NGF/SiO2/Si i hoʻololi ʻia ma mua o FS-NGF/SiO2/Si me nā waiwai rms o 140 nm a me 17 nm, e like me ka mea i hōʻike ʻia ma ke Kiʻi SI6a a me b (20 × 20 μm2). ʻO ka waiwai RMS o NGF i hoʻoili ʻia ma ka substrate SiO2/Si (RMS <2 nm) ʻoi aku ka haʻahaʻa (e pili ana i 3 mau manawa) ma mua o ka NGF i ulu ma Ni (Figure SI2), e hōʻike ana e pili ana ke ʻano koʻikoʻi me ka ʻili Ni. Eia kekahi, ua hōʻike ʻia nā kiʻi AFM ma nā ʻaoʻao o FS- a me BS-NGF / SiO2 / Si i nā mānoanoa NGF o 100 a me 80 nm, i kēlā me kēia (Fig. SI7). ʻO ka mānoanoa liʻiliʻi o BS-NGF ma muli paha o ka ʻike ʻole ʻia o ka ʻili i ke kinoea precursor.
Hoʻololi ʻia ʻo NGF (NiAG) me ka polymer ma SiO2 / Si wafer (e nānā i ke kiʻi 2c): (a, b) Nā kiʻi SEM o ka FS-NGF i hoʻoili ʻia: haʻahaʻa a kiʻekiʻe ka hoʻonui ʻia (e pili ana i ka huina alani i ka pā). Nā wahi maʻamau) – a). (c,d) Nā kiʻi SEM o ka BS-NGF i hoʻoili ʻia: ka hoʻonui haʻahaʻa a me ke kiʻekiʻe (e pili ana i ka ʻāpana maʻamau i hōʻike ʻia e ka huina alani ma ka panel c). (e, f) Nā kiʻi AFM o nā FS- a me BS-NGF i hoʻoili ʻia. Hōʻike ka pua ʻulaʻula i ka ʻāina FLG - ʻokoʻa ʻālohilohi, pua cyan - ʻokoʻa MLG ʻeleʻele, pua ʻulaʻula - ʻo ka ʻokoʻa ʻeleʻele e hōʻike ana i ka ʻāpana NGF, ʻo ka pua magenta ka pā.
Ua kālailai ʻia ka haku mele o nā FS- a me BS-NGF i ulu a hoʻoili ʻia e ka X-ray photoelectron spectroscopy (XPS) (Fig. 4). Uaʻikeʻia kahi kiʻekiʻe nāwaliwali i ka spectra i anaʻia (Fig. 4a, b), e pili ana i ka Ni substrate (850 eV) o ka ulu FS- a me BS-NGFs (NiAG). ʻAʻohe peaks i ka spectra ana o FS- a me BS-NGF / SiO2 / Si (Fig. 4c; ʻaʻole i hōʻike ʻia nā hopena like no BS-NGF / SiO2 / Si), e hōʻike ana ʻaʻohe koena Ni contamination ma hope o ka hoʻoili ʻana. . Hōʻike nā kiʻi 4d-f i ke kiʻekiʻe kiʻekiʻe o ka C 1 s, O 1 s a me Si 2p ikehu pae o FS-NGF/SiO2/Si. ʻO ka ikehu hoʻopaʻa o C 1 s o ka graphite he 284.4 eV53.54. ʻO ke ʻano laina o nā piko graphite ka mea maʻamau i manaʻo ʻia he asymmetrical, e like me ka hōʻike ʻana ma ke Kiʻi 4d54. Ua hoʻokūpaʻa pū ʻia ka hoʻololi maʻemaʻe (ʻo ia hoʻi, ʻaʻohe koena polymer), i kūlike me nā haʻawina mua38. ʻO nā laina laina o ka C 1 s spectra o ka mea kanu hou (NiAG) a ma hope o ka hoʻololi ʻana he 0.55 a me 0.62 eV. ʻOi aku kēia mau waiwai ma mua o ko SLG (0.49 eV no SLG ma kahi substrate SiO2)38. Eia nō naʻe, ʻoi aku ka liʻiliʻi o kēia mau waiwai ma mua o nā laina laina i hōʻike mua ʻia no nā laʻana pyrolytic graphene kiʻekiʻe (~ 0.75 eV) 53,54,55, e hōʻike ana i ka nele o nā wahi kalapona kīnā ʻole i ka mea o kēia manawa. ʻAʻole nā poʻohiwi o ka C 1 s a me O 1 s, e hoʻopau ana i ka pono no ka deconvolution kiʻekiʻe kiʻekiʻe. Aia kahi piko ukali π → π* ma kahi o 291.1 eV, i ʻike pinepine ʻia i nā laʻana graphite. ʻO nā hōʻailona 103 eV a me 532.5 eV i ka Si 2p a me O 1 s core level spectra (e nānā i ke kiʻi 4e, f) ua pili i ka substrate SiO2 56, kēlā me kēia. ʻO ka XPS kahi ʻano hana ʻike maka, no laila ua manaʻo ʻia nā hōʻailona e pili ana iā Ni a me SiO2 ma mua a ma hope o ka hoʻoili ʻana o NGF, kēlā me kēia, ua manaʻo ʻia mai ka ʻāina FLG. Ua ʻike ʻia nā hopena like no ka hoʻololi ʻana i nā laʻana BS-NGF (ʻaʻole i hōʻike ʻia).
Nā hualoaʻa o NiAG XPS: (ac) Nānā i nā kikoʻī o nā hui atomika elemental like ʻole o FS-NGF/Ni, BS-NGF/Ni a hoʻoili ʻia ʻo FS-NGF/SiO2/Si. (d–f) Kiʻekiʻe-hoʻonā kikoo o nā kumu nui C 1 s, O 1s a me Si 2p o ka FS-NGF/SiO2/Si hāpana.
Ua loiloi ʻia ka maikaʻi holoʻokoʻa o nā kristal NGF i hoʻololi ʻia me ka hoʻohana ʻana i ka X-ray diffraction (XRD). Hōʻike nā hiʻohiʻona XRD maʻamau (Fig. SI8) o ka FS- a me BS-NGF / SiO2 / Si i hoʻoili ʻia i ka hele ʻana o nā peaks diffraction (0 0 0 2) a me (0 0 0 4) ma 26.6 ° a me 54.7 °, e like me ka graphite. . Hōʻoia kēia i ka maikaʻi crystalline kiʻekiʻe o NGF a pili i kahi mamao interlayer o d = 0.335 nm, i mālama ʻia ma hope o ka neʻe ʻana. ʻO ka ikaika o ka peak diffraction (0 0 0 2) ma kahi o 30 mau manawa ma mua o ke kiʻekiʻe o ka diffraction (0 0 0 4), e hōʻike ana ua pili maikaʻi ka mokulele aniani NGF me ka ʻili hoʻohālike.
Wahi a nā hopena o SEM, Raman spectroscopy, XPS a me XRD, ua ʻike ʻia ka maikaʻi o BS-NGF/Ni e like me ka FS-NGF/Ni, ʻoiai ʻoi aku ka kiʻekiʻe o kona rms roughness (Figures SI2, SI5) a me SI7).
Hiki i nā SLG me nā papa kākoʻo polymer a hiki i ka 200 nm mānoanoa ke lana ma ka wai. Hoʻohana maʻamau ʻia kēia hoʻonohonoho i nā kaʻina hoʻololi kemika pulu i kōkua ʻia e polymer22,38. He hydrophobic ka Graphene a me ka graphite (koki pulu 80–90°) 57 . Ua hōʻike ʻia nā ʻili o ka ikehu o graphene a me FLG he palahalaha loa, me ka ikehu haʻahaʻa (~1 kJ/mol) no ka neʻe ʻana o ka wai ma ka ʻili58. Eia naʻe, ʻo ka ikehu pili o ka wai me ka graphene a me ʻekolu papa o ka graphene ma kahi o -13 a me -15 kJ/mol,58 i kēlā me kēia, e hōʻike ana he haʻahaʻa ka pilina o ka wai me NGF (ma kahi o 300 mau papa) i ka graphene. ʻO kēia paha kekahi o nā kumu e paʻa mau ai ka NGF kūʻokoʻa ma ka ʻili o ka wai, ʻoiai ʻo ka graphene kūʻokoʻa (e lana ana i loko o ka wai) e wili a wāwahi i lalo. Ke hoʻokomo piha ʻia ʻo NGF i ka wai (ua like nā hopena no ka NGF ʻala a me ka palahalaha), piʻo kona mau ʻaoʻao (Figure SI4). I ka hihia o ka piha immersion, ka mea, ua manaoia i ka NGF-wai pili ikehu ua aneane papalua (hoʻohālikelike i ka lana NGF) a me na lihi o ka NGF paʻa e malama i ka kiʻekiʻe pili kihi (hydrophobicity). Ke manaʻoʻiʻo nei mākou e hiki ke hoʻomohala ʻia nā hoʻolālā e pale aku i ka wili ʻana o nā kihi o nā NGF i hoʻokomo ʻia. ʻO kekahi ala ʻo ka hoʻohana ʻana i nā mea hoʻoheheʻe hui ʻia e hoʻololi i ka hoʻoheheʻe ʻana o ke kiʻi graphite59.
Ua hōʻike mua ʻia ka hoʻoili ʻana o SLG i nā ʻano substrates ma o nā kaʻina hoʻololi kemika pulu. Ua ʻae ʻia ʻo nā ikaika van der Waals nāwaliwali ma waena o nā kiʻi ʻoniʻoni graphene/graphite a me nā substrates (ʻo ia nā substrates paʻa e like me SiO2/Si38,41,46,60, SiC38, Au42, Si pillars22 a me nā kiʻi kalapona lacy30, 34 a i ʻole nā substrate maʻalahi. e like me polyimide 37). Maʻaneʻi, manaʻo mākou ʻoi aku ka nui o nā pilina o ka ʻano like. ʻAʻole mākou i ʻike i ka pōʻino a i ʻole ka ʻili ʻana o NGF no kekahi o nā substrate i hōʻike ʻia ma ʻaneʻi i ka wā o ka lawelawe ʻana i ka mīkini (i ka wā o ka hōʻike ʻana ma lalo o ka momi a / a i ʻole nā kūlana lewa a i ʻole i ka wā mālama) (e laʻa, Kiʻi 2, SI7 a me SI9). Eia hou,ʻaʻole mākou iʻike i kahi kiʻekiʻe SiC ma ka XPS C 1 s spectrum o ka pae kumu o ka NGF / SiO2 / Si sample (Fig. 4). Hōʻike kēia mau hopena ʻaʻohe paʻa kemika ma waena o NGF a me ka substrate i hoʻopaʻa ʻia.
Ma ka pauku mua, "Polymer-free transfer of FS- and BS-NGF," ua hōʻike mākou e hiki ke ulu a hoʻololi i ka NGF ma nā ʻaoʻao ʻelua o ka nickel foil. ʻAʻole like kēia mau FS-NGF a me BS-NGF ma ke ʻano o ka ʻili o ka ʻili, ka mea i koi iā mākou e ʻimi i nā noi kūpono loa no kēlā me kēia ʻano.
Ke noʻonoʻo nei i ka ʻike a me ka maʻalahi o ka ʻili o FS-NGF, ua aʻo mākou i kona ʻano kūloko, optical a me nā waiwai uila i nā kikoʻī hou aku. Ua ʻike ʻia ke ʻano a me ke ʻano o FS-NGF me ka hoʻololi ʻole o ka polymer e ka hoʻouna ʻana i ka microscopy electron (TEM) imaging a me ka nānā ʻana i ke ʻano o ka ʻāpana electron diffraction (SAED). Hōʻike ʻia nā hopena e pili ana i ka Figure 5. Ua hōʻike ʻia ke kiʻi kiʻi TEM planar haʻahaʻa i ka loaʻa ʻana o nā wahi NGF a me FLG me nā hiʻohiʻona like ʻole electron, ʻo ia hoʻi nā wahi ʻeleʻele a ʻoi aku ka mālamalama (Fig. 5a). Hōʻike ka kiʻiʻoniʻoni holoʻokoʻa i ka pono mechanical maikaʻi a me ke kūpaʻa ma waena o nā ʻāpana like ʻole o NGF a me FLG, me ka uhi maikaʻi a ʻaʻohe pōʻino a uhae paha, i hōʻoia pū ʻia e SEM (Figure 3) a me nā haʻawina TEM kiʻekiʻe (Figure 5c-e). ʻO ka mea nui, ma ka Fig. Figure 5d e hōʻike ana i ke ʻano o ke alahaka ma kona ʻāpana nui loa (ke kūlana i hōʻailona ʻia e ka pua ʻeleʻele ma ka Figure 5d), kahi i hōʻike ʻia e kahi ʻano triangular a loaʻa kahi papa graphene me kahi ākea o 51. Hoʻemi hou ʻia ka haku mele me ka spacing interplanar o 0.33 ± 0.01 nm i kekahi mau papa graphene ma ka ʻāpana haiki loa (hopena o ka pua ʻeleʻele paʻa ma ke Kiʻi 5 d).
Planar TEM kiʻi o ka polymer-free NiAG laʻana ma ka carbon lacy copper grid: (a, b) Nā kiʻi TEM hoʻonui haʻahaʻa me nā ʻāpana NGF a me FLG, (ce) ʻO nā kiʻi hoʻonui kiʻekiʻe o nā ʻāpana like ʻole ma ka panel-a a me ka panel-b. nā pua i kaha ʻia o ke kala like. Hōʻike nā pua ʻōmaʻomaʻo ma nā panela a me c i nā wahi pōʻai o ka pōʻino i ka wā o ka hoʻopololei ʻana. (f–i) Ma nā panela a i ka c, hōʻike ʻia nā mamana SAED ma nā ʻāpana like ʻole e nā pōʻai uliuli, cyan, ʻalani, a me ka ʻulaʻula.
Hōʻike ka lipine i ka Figure 5c (i hōʻailona ʻia me ka pua ʻulaʻula) i ke ʻano kū pololei o nā mokulele graphite lattice, ʻo ia paha ma muli o ka hoʻokumu ʻana o nā nanofolds ma ke kiʻi (hoʻokomo ʻia i ka Figure 5c) ma muli o ke koʻikoʻi o ka shear i uku ʻole ʻia30,61,62 . Ma lalo o TEM hoʻonā kiʻekiʻe, hōʻike kēia mau nanofolds 30 i kahi ʻano crystallographic ʻē aʻe ma mua o ke koena o ka ʻāina NGF; ʻO nā mokulele basal o ka lattice graphite ua hoʻonohonoho pono ʻia ma kahi kokoke i ka ʻaoʻao, ma mua o ka hoʻopaʻa ʻana e like me ke koena o ke kiʻiʻoniʻoni (hoʻokomo ʻia ma ke Kiʻi 5c). Pēlā nō, hōʻike ʻia ka ʻāina FLG i kekahi manawa i nā ʻāpana like ʻole a me nā ʻāpana liʻiliʻi (i hōʻailona ʻia e nā pua polū), e ʻike ʻia ma ka hoʻonui haʻahaʻa a me ka liʻiliʻi ma nā Kiʻi 5b, 5e, kēlā me kēia. ʻO ka hoʻokomo ʻana i ka Figure 5e e hōʻoia i ka loaʻa ʻana o nā papa graphene ʻelua a ʻekolu-papa ma ka ʻāpana FLG (ka mamao interplanar 0.33 ± 0.01 nm), i ʻaelike maikaʻi me kā mākou hopena mua30. Hoʻohui ʻia, hōʻike ʻia nā kiʻi SEM i hoʻopaʻa ʻia o ka NGF polimer-ʻole i hoʻoili ʻia ma nā pahu keleawe me nā kiʻi kalapona lacy (ma hope o ka hana ʻana i nā ana TEM kiʻekiʻe) e hōʻike ʻia ma ke Kiʻi SI9. ʻO ka ʻāina FLG maikaʻi i hoʻokuʻu ʻia (i hōʻailona ʻia me ka pua polū) a me ka ʻāpana haʻihaʻi ma ke Kiʻi SI9f. Hōʻike ʻia ka pua polū (ma ka lihi o ka NGF i hoʻoili ʻia) e hōʻike i ka hiki i ka ʻāina FLG ke pale i ke kaʻina hana me ka polymer. I ka hōʻuluʻulu ʻana, ua hōʻoia kēia mau kiʻi i ka NGF i hoʻokuʻu ʻia (me ka ʻāina FLG) e mālama i ka pono mechanical ma hope o ka hoʻopaʻa ʻana a me ka ʻike ʻana i ka moena kiʻekiʻe i nā ana TEM a me SEM (Figure SI9).
Ma muli o ka palahalaha maikaʻi loa o NGF (e nānā i ke kiʻi 5a), ʻaʻole paʻakikī ke hoʻonohonoho ʻana i nā flakes ma ka axis domain [0001] e nānā i ke ʻano SAED. Ma muli o ka mānoanoa kūloko o ke kiʻiʻoniʻoni a me kona wahi, ua ʻike ʻia kekahi mau wahi hoihoi (12 mau helu) no nā haʻawina ʻokoʻa electron. Ma nā Kiʻi 5a–c, hōʻike ʻia ʻehā o kēia mau ʻāpana maʻamau a kaha ʻia me nā pōʻai waihoʻoluʻu (uliuli, cyan, ʻalani, a me ka ʻulaʻula). Nā kiʻi 2 a me 3 no ke ʻano SAED. Ua loaʻa nā kiʻi 5f a me g mai ka māhele FLG i hōʻike ʻia ma nā kiʻi 5 a me 5. E like me ka mea i hōʻike ʻia ma nā kiʻi 5b a me c. He ʻano hexagonal ko lākou e like me ka graphene63 wili. ʻO ka mea nui, hōʻike ka Figure 5f i ʻekolu mau hiʻohiʻona superimposed me ke ʻano like o ke axis zone [0001], i hoʻololi ʻia e 10° a me 20°, e like me ka hōʻike ʻia e ka like ʻole o ka angular o nā hui ʻekolu o (10-10). Pēlā nō, hōʻike ka Figure 5g i ʻelua mau hiʻohiʻona hexagonal superimposed i hoʻololi ʻia e 20°. ʻElua a ʻekolu pūʻulu o nā ʻano hexagonal ma ka ʻāina FLG hiki ke ala mai ʻekolu mau papa graphene i loko o ka mokulele a i waho paha o ka mokulele 33 i hoʻololi ʻia e pili ana i kekahi. ʻO ka hoʻohālikelike ʻana, ʻo nā hiʻohiʻona electron diffraction ma ke Kiʻi 5h,i (e pili ana i ka ʻāpana NGF i hōʻike ʻia ma ka Figure 5a) e hōʻike i kahi kumu hoʻokahi [0001] me kahi kiʻekiʻe kiʻekiʻe kiʻekiʻe o ka diffraction ikaika, e pili ana i ka mānoanoa mea nui. ʻO kēia mau hiʻohiʻona SAED e pili ana i kahi hoʻolālā graphitic mānoanoa a me ka ʻaoʻao waena ma mua o FLG, e like me ka mea i ʻike ʻia mai ka index 64. ʻO ke ʻano o nā waiwai crystalline o NGF i hōʻike ʻia i ka noho pū ʻana o ʻelua a ʻekolu paha graphite (a i ʻole graphene) crystallites. ʻO ka mea nui loa i ka ʻāina FLG ʻo ia ka loaʻa ʻana o nā crystallites i kahi degere o ka misorientation i loko o ka mokulele a i waho paha o ka mokulele. Ua hōʻike mua ʻia nā ʻāpana graphite / ʻāpana me nā kihi rotation in-plane o 17 °, 22 ° a me 25 ° no NGF i ulu ma Ni 64 kiʻiʻoniʻoni. ʻO nā koina hulina hulina i ʻike ʻia i loko o kēia haʻawina e kūlike me nā kihi hulina i ʻike mua ʻia (± 1°) no ka graphene BLG63 wili.
Ua ana ʻia nā waiwai uila o NGF/SiO2/Si ma 300 K ma kahi o 10 × 3 mm2. ʻO nā kumukūʻai o ka hoʻokele uila uila, ka neʻe a me ka conductivity he 1.6 × 1020 cm-3, 220 cm2 V-1 C-1 a me 2000 S-cm-1. Ua like ka mobility a me ka conductivity o kā mākou NGF me ka graphite2 maoli a ʻoi aku ka kiʻekiʻe ma mua o ka graphite pyrolytic kiʻekiʻe i loaʻa i ke kālepa (i hana ʻia ma 3000 °C)29. ʻO nā koina hoʻokele electron i ʻike ʻia he ʻelua mau kauoha o ka nui ma mua o nā mea i hōʻike ʻia nei (7.25 × 10 cm-3) no nā kiʻi graphite micron-mānoanoa i hoʻomākaukau ʻia me ka hoʻohana ʻana i nā pepa polyimide kiʻekiʻe (3200 °C) 20.
Ua hana pū mākou i nā ana transmittance ʻike UV ma FS-NGF i hoʻoili ʻia i nā substrates quartz (Figure 6). Hōʻike ka spectrum hopena i kahi transmittance kokoke mau o 62% ma ka laulā 350-800 nm, e hōʻike ana he translucent NGF i ka mālamalama ʻike. ʻOiaʻiʻo, hiki ke ʻike ʻia ka inoa "KAUST" ma ke kiʻi kikohoʻe o ka laʻana ma ke Kiʻi 6b. ʻOiai ʻokoʻa ke ʻano nanocrystalline o NGF mai ka SLG, hiki ke helu ʻia ka helu o nā papa me ka hoʻohana ʻana i ke kānāwai o 2.3% ka nalowale o ka lawe ʻana i kēlā me kēia layer65. Wahi a kēia pilina, ʻo ka helu o nā papa graphene me 38% ka nalowale o ka hoʻouna ʻana he 21. ʻO ka NGF ulu nui he 300 mau papa graphene, ʻo ia hoʻi ma kahi o 100 nm mānoanoa (Fig. 1, SI5 a me SI7). No laila, ke manaʻo nei mākou e pili ana ka ʻike ʻike ʻike ʻia me nā ʻāpana FLG a me MLG, no ka mea ua puʻunaue ʻia lākou i loko o ke kiʻiʻoniʻoni (Fig. 1, 3, 5 a me 6c). Ma waho aʻe o ka ʻikepili i hoʻonohonoho ʻia ma luna, ka conductivity a me ka ʻike maopopo e hōʻoia i ka maikaʻi crystalline kiʻekiʻe o ka NGF i hoʻoili ʻia.
(a) Ana hoʻoili uila ʻike ʻia, (b) hoʻololi NGF maʻamau ma ka quartz me ka hoʻohana ʻana i kahi laʻana. (c) Schematic of NGF (pahu ʻeleʻele) me ka māhele like ʻana o nā ʻāpana FLG a me MLG i kaha ʻia ma ke ʻano he mau hiʻohiʻona hina hina i loko o ka hāpana (e nānā i ke Kiʻi 1) (ma kahi o 0.1-3% ʻāpana no 100 μm2). ʻO nā ʻano like ʻole a me ko lākou nui ma ke kiʻikuhi no nā kumu hoʻohālike wale nō a ʻaʻole i kūpono i nā wahi maoli.
ʻO Translucent NGF i ulu ʻia e CVD ua hoʻoneʻe mua ʻia i nā ʻili silika ʻole a hoʻohana ʻia i nā cell solar15,16. ʻO ka hopena o ka hoʻololi ʻana i ka mana (PCE) he 1.5%. Hana kēia mau NGF i nā hana he nui e like me nā papa hana hoʻohuihui, nā ala lawe ukana, a me nā electrodes maopopo15,16. Eia naʻe, ʻaʻole like ke kiʻi graphite. Pono ka hoʻonui hou ʻana ma ka mālama pono ʻana i ka pale pale a me ka transmittance optical o ka electrode graphite, no ka mea he mea nui kēia mau waiwai ʻelua i ka hoʻoholo ʻana i ka waiwai PCE o ka cell solar15,16. ʻO ka maʻamau, ʻo nā kiʻi ʻoniʻoni graphene he 97.7% akaka i ka mālamalama ʻike ʻia, akā he 200–3000 ohms/sq.16 ka pale pale. Hiki ke hoemiia ke ku o ka ili o na kii graphene ma ka hoonui ana i ka nui o na papa (ka hoololi ana o na papa graphene) a me ka doping me HNO3 (~ 30 Ohm/sq.)66. Eia naʻe, lōʻihi kēia kaʻina hana a ʻaʻole mālama mau nā papa hoʻoili like ʻole i ka pilina maikaʻi. Loaʻa i kā mākou ʻaoʻao mua NGF nā waiwai e like me ka conductivity 2000 S / cm, pale pale kiʻi 50 ohm / sq. a me 62% transparency, e lilo ia i mea kūpono no nā ala conductive a i ʻole nā electrodes counter i loko o nā cell solar15,16.
ʻOiai ua like ke ʻano a me ka kemika ʻili o BS-NGF me FS-NGF, ʻokoʻa kona ʻano ʻino ("Growth of FS- and BS-NGF"). Ma mua, ua hoʻohana mākou i ka ultra-thin film graphite22 ma ke ʻano he mea ʻike kinoea. No laila, ua hoʻāʻo mākou i ka hiki ke hoʻohana i ka BS-NGF no nā hana ʻike kinoea (Figure SI10). ʻO ka mua, ua hoʻoneʻe ʻia nā ʻāpana mm2-nui o BS-NGF ma ka interdigitating electrode sensor chip (Figure SI10a-c). Ua hōʻike mua ʻia nā kikoʻī hana o ka chip; ʻO 9 mm267 kona wahi koʻikoʻi. Ma nā kiʻi SEM (Figure SI10b a me c), ʻike maopopo ʻia ka electrode gula ma lalo o ka NGF. Eia hou, hiki ke ʻike ʻia ua hoʻokō ʻia ka uhi ʻana o ka chip no nā laʻana āpau. Ua hoʻopaʻa ʻia nā ana ʻike kinoea o nā kinoea like ʻole (Fig. SI10d) (Fig. SI11) a ua hōʻike ʻia nā helu pane o ka hopena ma Fig. SI10g. Me nā kinoea hoʻopilikia ʻē aʻe e like me SO2 (200 ppm), H2 (2%), CH4 (200 ppm), CO2 (2%), H2S (200 ppm) a me NH3 (200 ppm). ʻO kekahi kumu kumu ʻo NO2. ano electrophilic o ke kinoea22,68. Ke hoʻopili ʻia ma ka ʻili o ka graphene, hoʻemi ia i ka absorption o nā electrons i kēia manawa e ka ʻōnaehana. Hōʻike ʻia kahi hoʻohālikelike o ka ʻikepili manawa pane o ka sensor BS-NGF me nā mea i paʻi mua ʻia ma ka Papa SI2. Ke hoʻomau nei ka hana no ka hoʻoulu hou ʻana i nā mea ʻike NGF me ka hoʻohana ʻana i ka plasma UV, ka plasma O3 a i ʻole ka wela (50-150°C) i ka mālama ʻana i nā laʻana i hōʻike ʻia, e ukali ʻia e ka hoʻokō ʻana i nā ʻōnaehana i hoʻokomo ʻia69.
Ma ke kaʻina hana CVD, ulu ka graphene ma nā ʻaoʻao ʻelua o ka substrate catalyst41. Eia naʻe, hoʻokuʻu pinepine ʻia ʻo BS-graphene i ka wā o ka hoʻoili ʻana41. Ma kēia haʻawina, hōʻike mākou e hiki ke hoʻokō ʻia ka ulu ʻana o ka NGF kiʻekiʻe a me ka polymer-free NGF ma nā ʻaoʻao ʻelua o ke kākoʻo catalyst. ʻOi aku ka lahilahi o BS-NGF (~ 80 nm) ma mua o FS-NGF (~ 100 nm), a ua wehewehe ʻia kēia ʻokoʻa e ka ʻike ʻole ʻana o BS-Ni i ke kahe kinoea precursor. Ua ʻike pū mākou ʻo ke koʻikoʻi o ka substrate NiAR e hoʻopili i ka ʻino o ka NGF. Hōʻike kēia mau hopena e hiki ke hoʻohana ʻia ka planar FS-NGF ma ke ʻano he mea precursor no ka graphene (ma ka exfoliation method70) a i ʻole he ala conductive i nā cell solar15,16. ʻO ka ʻokoʻa, e hoʻohana ʻia ʻo BS-NGF no ka ʻike kinoea (Fig. SI9) a malia paha no nā ʻōnaehana mālama ikehu71,72 kahi e pono ai kona ʻano ʻili.
Ma ka noʻonoʻo ʻana i luna, pono e hoʻohui i ka hana o kēia manawa me nā kiʻi graphite i paʻi mua ʻia i ulu ʻia e CVD a me ka hoʻohana ʻana i ka nickel foil. E like me ka mea i ʻike ʻia ma ka Papa 2, ʻo nā kaomi kiʻekiʻe a mākou i hoʻohana ai i hoʻopōkole i ka manawa pane (ka wā ulu) ʻoiai me nā haʻahaʻa haʻahaʻa (ma ka laulā o 850–1300 °C). Ua hoʻokō pū mākou i ka ulu nui ma mua o ka mea maʻamau, e hōʻike ana i ka hiki ke hoʻonui. Aia kekahi mau kumu ʻē aʻe e noʻonoʻo ai, ʻo kekahi o ia mau mea a mākou i hoʻokomo ai i ka papa.
Ua ulu ʻia ka NGF kiʻekiʻe ʻelua ʻaoʻao ma luna o ka nickel foil e catalytic CVD. Ma ka hoʻopau ʻana i nā substrate polymer kuʻuna (e like me nā mea i hoʻohana ʻia ma CVD graphene), loaʻa iā mākou ka hoʻololi ʻana i ka maʻemaʻe a me ke kīnā ʻole o NGF (ulu ma ke kua a me nā ʻaoʻao mua o ka nickel foil) i nā ʻano substrates koʻikoʻi kaʻina. ʻO ka mea nui, loaʻa i ka NGF nā ʻāpana FLG a me MLG (maʻamau 0.1% a 3% no 100 µm2) i hoʻohui maikaʻi ʻia i loko o ke kiʻiʻoniʻoni mānoanoa. Hōʻike ka Planar TEM ua haku ʻia kēia mau ʻāpana me nā pūʻulu o ʻelua a ʻekolu mau ʻāpana graphite/graphene (nā kristal a i ʻole nā papa, kēlā me kēia), ʻo kekahi o ia mau mea he 10-20° ka hoʻololi ʻana. ʻO nā ʻāpana FLG a me MLG ke kuleana no ka ʻike ʻia o FS-NGF i ka mālamalama ʻike. No nā ʻāpana hope, hiki ke lawe like ʻia me nā ʻaoʻao mua a, e like me ka mea i hōʻike ʻia, hiki ke loaʻa kahi kumu hana (no ka laʻana, no ka ʻike kinoea). He mea maikaʻi loa kēia mau haʻawina no ka hōʻemi ʻana i ka ʻōpala a me nā kumukūʻai i nā kaʻina hana CVD pālākiō ʻoihana.
Ma keʻano laulā, aia ka mānoanoa awelika o CVD NGF ma waena o (haʻahaʻa a me multi-layer) graphene a me ka ʻenehana (micrometer) graphite pepa. ʻO ka laulā o kā lākou mau waiwai hoihoi, i hui pū ʻia me ke ʻano maʻalahi a mākou i hoʻomohala ai no kā lākou hana ʻana a me ka lawe ʻana, ua kūpono kēia mau kiʻiʻoniʻoni no nā noi e koi ana i ka pane hana o ka graphite, me ka uku ʻole o nā kaʻina hana ʻenehana ikaika i hoʻohana ʻia i kēia manawa.
Ua hoʻokomo ʻia kahi nickel foil 25-μm-mānoanoa (99.5% purity, Goodfellow) i loko o kahi reactor CVD kalepa (Aixtron 4-inch BMPro). Hoʻomaʻemaʻe ʻia ka ʻōnaehana me ka argon a hoʻokuʻu ʻia i kahi kumu kumu o 10-3 mbar. A laila kau ʻia ka nickel foil. ma Ar / H2 (Ma hope o ka hoʻopili muaʻana i ka Ni foil no 5 min, uaʻikeʻia ka pahu i kahi kaomi o 500 mbar ma 900 ° C. Ua waihoʻiaʻo NGF i kahi kahe o CH4 / H2 (100 cm3 i kēlā me kēia) no 5 min. A laila ua hoʻomālili ʻia ka laʻana i ka mahana ma lalo o 700 °C me ka hoʻohana ʻana i ke kahe Ar (4000 cm3) ma 40 °C/min Ua wehewehe ʻia nā kikoʻī e pili ana i ka hoʻonui ʻana i ke kaʻina ulu NGF.
ʻIke ʻia ka morphology ili o ka hāpana e SEM me ka microscope Zeiss Merlin (1 kV, 50 pA). Ua ana ʻia ka mānoanoa o ka ʻili a me ka mānoanoa NGF me ka hoʻohana ʻana i ka AFM (Dimension Icon SPM, Bruker). Ua hana ʻia nā ana TEM a me SAED me ka FEI Titan 80–300 Cubed microscope i lako me kahi pū puhi hoʻoheheʻe kiʻekiʻe (300 kV), kahi monochromator ʻano FEI Wien a me kahi mea hoʻoponopono aberration spherical lens CEOS no ka loaʻa ʻana o nā hopena hope. 0.09 nm ka hoʻonā kiko. Ua hoʻoili ʻia nā laʻana NGF i nā pahu keleawe kalapona i uhi ʻia no ka kiʻi TEM palahalaha a me ka nānā ʻana i ka hoʻolālā SAED. No laila, ua hoʻokuʻu ʻia ka hapa nui o nā flocs hāpana i nā pores o ka membrane kākoʻo. Ua kālailai ʻia nā laʻana NGF i hoʻoili ʻia e XRD. Ua kiʻi ʻia nā kumu hoʻohālikelike X-ray me ka hoʻohana ʻana i kahi diffractometer pauka (Brucker, D2 phase shifter me Cu Kα kumu, 1.5418 Å a me LYNXEYE detector) me ka hoʻohana ʻana i kahi kumu hoʻoheheʻe Cu me kahi anawaena wahi kaola o 3 mm.
Ua hoʻopaʻa ʻia kekahi mau ana helu Raman me ka hoʻohana ʻana i kahi microscope confocal hoʻohui (Alpha 300 RA, WITeC). Ua hoʻohana ʻia kahi laser 532 nm me ka mana excitation haʻahaʻa (25%) e pale i nā hopena i hoʻokomo ʻia i ka wela. Ua hana ʻia ka X-ray photoelectron spectroscopy (XPS) ma kahi Kratos Axis Ultra spectrometer ma luna o kahi laʻana o 300 × 700 μm2 me ka hoʻohana ʻana i ka radiation Al Kα monochromatic (hν = 1486.6 eV) ma ka mana o 150 W. Loaʻa ʻia ka spectra hoʻonā ma nā mana hoʻoili o 160 eV a me 20 eV, kēlā me kēia. Ua ʻoki ʻia nā ʻāpana NGF i hoʻoili ʻia ma SiO2 i ʻāpana (3 × 10 mm2 kēlā me kēia) me ka hoʻohana ʻana i ka laser fiber ytterbium ytterbium PLS6MW (1.06 μm) ma 30 W. Ua hana ʻia nā mea hoʻopili uea keleawe (50 μm mānoanoa) me ka hoʻohana ʻana i ka paʻi kālā ma lalo o kahi microscope optical. Ua lawe ʻia nā hoʻokolohua uila a me nā hopena Hall ma kēia mau laʻana ma 300 K a me kahi hoʻololi ʻana o ke kahua magnetic o ± 9 Tesla i kahi ʻōnaehana ana waiwai kino (PPMS EverCool-II, Quantum Design, USA). Ua hoʻopaʻa ʻia ka spectra UV-vis i hoʻouna ʻia me ka Lambda 950 UV-vis spectrophotometer ma ka laulā 350-800 nm NGF i hoʻoili ʻia i nā substrates quartz a me nā laʻana kuhikuhi quartz.
Ua hoʻopaʻa ʻia ka mea ʻike kūʻē kemika (interdigitated electrode chip) i kahi papa kaapuni paʻi maʻamau 73 a lawe ʻia ke kū'ē i ka manawa. Hoʻopili ʻia ka papa kaapuni i paʻi ʻia ma luna o ka mea hana i nā pauku pili a waiho ʻia i loko o ke keʻena ʻike kinoea. Ua hoʻomaʻemaʻe mua ʻia ke keʻena ma ka hoʻomaʻemaʻe ʻana me ka nitrogen ma 200 cm3 no 1 hola e hōʻoia i ka lawe ʻia ʻana o nā analytes ʻē aʻe a pau i loko o ke keʻena, me ka wai. Ua hoʻokuʻu mālie ʻia nā analytes pākahi i loko o ke keʻena ma ke kahe kahe like o 200 cm3 ma ka pani ʻana i ka cylinder N2.
Ua paʻi ʻia kahi mana hou o kēia ʻatikala a hiki ke kiʻi ʻia ma o ka loulou ma luna o ka ʻatikala.
Inagaki, M. a me Kang, F. Carbon Materials Science and Engineering: Fundamentals. Hoʻoponopono ʻia ka lua. 2014. 542.
Pearson, HO Handbook of Carbon, Graphite, Diamond and Fullerenes: Nā Pono, Hoʻoponopono a me nā noi. Ua hoʻoponopono ʻia ka paʻi mua. 1994, New Jersey.
Tsai, W. et al. Nā kiʻi ʻoniʻoni graphene/graphite multilayer nui e like me nā electrodes conductive lahilahi. palapala noi. physics. Wright. 95(12), 123115(2009).
ʻO Balandin AA nā waiwai wela o ka graphene a me nā mea kalapona i hoʻonohonoho ʻia. Nat. Mat. 10(8), 569–581 (2011).
ʻO Cheng KY, Brown PW a me Cahill DG ʻO ka hoʻokō wela o nā kiʻi graphite i ulu ma Ni (111) e ka hoʻoheheʻe ʻana i ka mahu kemika haʻahaʻa. adverb. Mat. Ili 3, 16 (2016).
Hesjedal, T. Ka ulu mau ʻana o nā kiʻiʻoniʻoni graphene ma ka waiho ʻana o ka mahu. palapala noi. physics. Wright. 98(13), 133106(2011).
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