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Ihe nkiri Nanoscale graphite (NGFs) bụ ihe nanomaterials siri ike nke enwere ike imepụta site na ntinye kemịkalụ kemịkalụ, mana ajụjụ ka dị maka ịdị mfe nke mbufe ha yana ka ọdịdị elu ala si emetụta ojiji ha na ngwaọrụ ọgbọ na-abịa. N'ebe a, anyị na-akọ na uto nke NGF n'akụkụ abụọ nke polycrystalline nickel foil (mpaghara 55 cm2, ọkpụrụkpụ banyere 100 nm) na nnyefe na-enweghị polymer (n'ihu na azụ, mpaghara ruo 6 cm2). N'ihi ọdịdị ọdịdị nke foil catalyst, ihe nkiri carbon abụọ ahụ dị iche na njirimara anụ ahụ ha na njirimara ndị ọzọ (dịka ọdịdị elu). Anyị na-egosi na NGF ndị nwere azụ azụ na-adabara nke ọma maka nchọpụta NO2, ebe NGF dị nro na ndị ọzọ na-eduzi n'ihu (2000 S / cm, mgbochi mpempe akwụkwọ - 50 ohms / m2) nwere ike ịbụ ndị na-eduzi. ọwa ma ọ bụ electrode nke cell anyanwụ (ebe ọ na-ebunye 62% nke ìhè a na-ahụ anya). N'ozuzu, usoro uto na njem a kọwara nwere ike inye aka ịghọta NGF dị ka ihe ọzọ carbon maka ngwa teknụzụ ebe ihe nkiri graphene na micron-thick graphite adịghị adabara.
Graphite bụ ihe eji emepụta ihe n'ọtụtụ ebe. N'ụzọ doro anya, graphite nwere njirimara nke njupụta dịtụ ala na ikuku ikuku na ikuku eletrik dị elu, ma kwụsie ike na gburugburu okpomọkụ na kemịkal siri ike1,2. Flake graphite bụ ihe mmalite ama ama maka nyocha graphene3. Mgbe etinyere ya na ihe nkiri dị mkpa, enwere ike iji ya n'ọtụtụ ngwa ngwa, gụnyere ikpo ọkụ maka ngwaọrụ eletrọnịkị dị ka smartphones4,5,6,7, dị ka ihe na-arụ ọrụ na sensọ8,9,10 na maka nchebe nnyonye anya electromagnetic11. 12 na ihe nkiri maka lithography na oke ultraviolet13,14, na-eduzi ọwa na sel anyanwụ15,16. Maka ngwa ndị a niile, ọ ga-abụ uru dị ịrịba ama ma ọ bụrụ na nnukwu akụkụ nke ihe nkiri graphite (NGFs) na ọkpụrụkpụ a na-achịkwa na nanoscale <100 nm nwere ike ịmepụta ma bufee ya ngwa ngwa.
A na-emepụta ihe nkiri graphite site na ụzọ dị iche iche. N'otu oge, ntinye na mgbasawanye nke na-esote exfoliation ejiri mee ihe iji mepụta flakes graphene10,11,17. A ghaghị ịhazigharị flakes ndị ahụ ka ọ bụrụ ihe nkiri nke ọkpụrụkpụ achọrọ, ọ na-ewekwa ọtụtụ ụbọchị iji mepụta mpempe akwụkwọ graphite. Ụzọ ọzọ bụ ịmalite site na ihe nrịbama siri ike na-ese foto. N'ime ụlọ ọrụ, a na-eme ka carbonized mpempe akwụkwọ nke polymers (na 1000-1500 Celsius C) wee graphitized (na 2800-3200 Celsius) iji mepụta ihe ndị a haziri nke ọma. Ọ bụ ezie na ịdị mma nke ihe nkiri ndị a dị elu, ike oriri dị ịrịba ama1,18,19 na nke kacha nta bụ nanị microns1,18,19,20.
Catalytic kemịkalụ vapor deposition (CVD) bụ usoro ama ama maka imepụta ihe nkiri graphene na ultrathin graphite (<10 nm) nwere ogo nhazi dị elu yana ọnụ ahịa ezi uche dị na ya21,22,23,24,25,26,27. Otú ọ dị, atụnyere uto nke graphene na ultrathin graphite film28, nnukwu-mpaghara ibu na/ma ọ bụ ngwa nke NGF iji CVD bụ ọbụna obere nnyocha 11,13,29,30,31,32,33.
graphene na ihe nkiri graphite tolitere CVD na-achọkarị ibufe na substrates na-arụ ọrụ34. Nfefe ihe nkiri ndị a dị mkpa gụnyere ụzọ abụọ bụ isi35: (1) mbufe na-abụghị etch36,37 na (2) mbufe kemịkalụ mmiri dabere na etch (mkpụrụ nkwado) 14,34,38. Usoro ọ bụla nwere ụfọdụ uru na ọghọm dị na a ga-ahọpụtarịrị dabere na ngwa ezubere, dịka akọwara ebe ọzọ35,39. Maka ihe nkiri graphene/graphite toro na mkpụrụ ndụ catalytic, nyefee site na usoro kemịkalụ mmiri (nke polymethyl methacrylate (PMMA) bụ ihe nkwado a na-ejikarị eme ihe) ka bụ nhọrọ mbụ13,30,34,38,40,41,42. Ị et al. Ekwuru na ọ dịghị polymer e ji mee ihe maka mbufe NGF (nha nhata dịka 4 cm2) 25,43, ma ọ dịghị nkọwa e nyere banyere nkwụsi ike sample na / ma ọ bụ njikwa n'oge nnyefe; Usoro kemịkalụ mmiri na-eji polymer nwere ọtụtụ usoro, gụnyere ngwa na mwepụ nke oyi akwa polymer na-esote30,38,40,41,42. Usoro a nwere ihe ọghọm: dịka ọmụmaatụ, ihe fọdụrụ na polymer nwere ike ịgbanwe ihe nke ihe nkiri toro eto38. Nhazi ndị ọzọ nwere ike wepu polymer fọdụrụnụ, mana usoro ndị a na-abawanye ọnụ ahịa na oge mmepụta ihe nkiri38,40. N'oge CVD na-eto eto, a na-edobe oyi akwa nke graphene ọ bụghị naanị n'akụkụ ihu nke foil catalyst (n'akụkụ chere ihu nkuku uzuoku), kamakwa n'akụkụ azụ ya. Agbanyeghị, a na-ewere nke ikpeazụ dị ka ihe mkpofu ma nwee ike wepu ya ngwa ngwa site na plasma dị nro38,41. Imegharị ihe nkiri a nwere ike inye aka ịbawanye mkpụrụ, ọbụlagodi na ọ dị ala karịa ihe nkiri carbon ihu.
N'ebe a, anyị na-akọ nkwadebe nke uto bifacial nke wafer-scale nke NGF nwere àgwà nhazi dị elu na polycrystalline nickel foil site na CVD. A tụlere ya ka isi ike nke ihu na azụ azụ nke foil si emetụta ọdịdị ọdịdị na nhazi nke NGF. Anyị na-egosipụtakwa na-enyefe NGF polymer-free na-akwụ ụgwọ na gburugburu ebe obibi site na akụkụ abụọ nke nickel foil na multifunctional substrates ma gosi otú ihe nkiri ihu na azụ si adabara maka ngwa dị iche iche.
Akụkụ ndị na-esonụ na-atụle ọkpụrụkpụ ihe nkiri graphite dị iche iche dabere na ọnụ ọgụgụ nke akwa akwa graphene: (i) otu oyi akwa graphene (SLG, 1 oyi akwa), (ii) graphene ole na ole (FLG, <10 layers), (iii) multilayer graphene ( MLG, 10-30 n'ígwé) na (iv) NGF (~ 300 n'ígwé). Nke ikpeazụ bụ ọkpụrụkpụ a na-ahụkarị egosipụtara dị ka pasent nke mpaghara (ihe dịka 97% mpaghara kwa 100 µm2)30. Ya mere a na-akpọ ihe nkiri ahụ dum NGF.
Polycrystalline nickel foils eji maka njikọ nke graphene na ihe nkiri graphite nwere textures dị iche iche n'ihi nrụpụta ha na nhazi ha na-esote. N'oge na-adịbeghị anya, anyị kọrọ otu ọmụmụ iji kwalite usoro uto nke NGF30. Anyị na-egosi na usoro usoro dịka oge nkwụsịtụ na nrụgide ụlọ n'oge uto na-arụ ọrụ dị oke mkpa n'inweta NGF nke nha nha. N'ebe a, anyị gara n'ihu nyochaa uto nke NGF na-egbuke egbuke n'ihu (FS) na azụ azụ (BS) na-ebupụta nke nickel foil (Fig 1a). A na-enyocha ụdị atọ nke ihe atụ FS na BS, ndị e depụtara na tebụl 1. N'elu nlele anya, uto nke NGF n'akụkụ abụọ nke nickel foil (NiAG) nwere ike ịhụ site na mgbanwe agba nke nnukwu mkpụrụ Ni site na ọlaọcha ọla mara mma. isi awọ na agba ntụ ntụ matte (Fig 1a); A kwadoro nha nke microscopic (Fig 1b, c). A na-ahụ ụdịdị dị iche iche nke Raman nke FS-NGF na mpaghara na-egbuke egbuke ma gosi site na ụta uhie, acha anụnụ anụnụ na oroma na eserese 1b na foto 1c. Ihe e ji mara Raman elu nke graphite G (1683 cm-1) na 2D (2696 cm-1) kwadoro uto nke NGF kristal dị elu (Fig 1c, Table SI1). N'ime ihe nkiri ahụ dum, a na-ahụta oke nke Raman spectra nwere oke ike (I2D/IG) ~ 0.3, ebe a na-ahụkarị spectra Raman nwere I2D/IG = 0.8. Enweghị ọnụ ọgụgụ ndị na-adịghị mma (D = 1350 cm-1) na fim ahụ dum na-egosi ogo dị elu nke uto NGF. Enwetara nsonaazụ Raman yiri nke ahụ na nlele BS-NGF (Foto SI1 a na b, Tebụl SI1).
Ntụle nke NiAG FS- na BS-NGF: (a) Foto nke ihe atụ NGF (NiAG) nke na-egosi uto NGF n'ọtụtụ wafer (55 cm2) na ihe nleba anya BS- na FS-Ni, (b) FS-NGF. Onyonyo/Ni nwetara site na microscope anya, (c) ụdị ihe nkiri Raman na-ahụkarị nke edere n'ọnọdụ dị iche iche na panel b, (d, f) onyonyo SEM n'ogo dị iche iche na FS-NGF/Ni, (e, g) onyonyo SEM na ọkwa dị iche iche. Tọọ BS -NGF/Ni. Akụ na-acha anụnụ anụnụ na-egosi mpaghara FLG, akụ oroma na-egosi mpaghara MLG (n'akụkụ mpaghara FLG), akụ na-acha uhie uhie na-egosi mpaghara NGF, na akụ magenta na-egosi mpịakọta ahụ.
Ebe ọ bụ na uto dabere na ọkpụrụkpụ nke mkpụrụ mbụ, nha kristal, nghazi, na oke ọka, inweta njikwa ezi uche dị na ọkpụrụkpụ NGF n'elu nnukwu mpaghara ka bụ ihe ịma aka20,34,44. Ọmụmụ ihe a jiri ọdịnaya anyị bipụtara na mbụ30. Usoro a na-emepụta mpaghara na-egbuke egbuke nke 0.1 ruo 3% kwa 100 µm230. Na ngalaba ndị a, anyị na-eweta nsonaazụ maka mpaghara abụọ ahụ. Ihe onyonyo SEM dị elu na-egosi ọnụnọ dị iche iche na-egbuke egbuke n'akụkụ abụọ (Fig 1f, g), na-egosi ọnụnọ FLG na MLG mpaghara30,45. A kwadoro nke a site na mgbasa ozi Raman (Fig 1c) na nsonaazụ TEM (tụlere n'ikpeazụ na ngalaba "FS-NGF: Ọdịdị na Njirimara"). Mpaghara FLG na MLG hụrụ na nlele FS- na BS-NGF/Ni (n'ihu na azụ NGF toro na Ni) nwere ike itolite na ọka Ni (111) buru ibu nke emere n'oge tupu annealing22,30,45. Ahụrụ mpịachi n'akụkụ abụọ (Fig 1b, akara akụ na-acha odo odo). A na-ahụkarị mpịachi ndị a na ihe nkiri graphene na graphite toro CVD n'ihi nnukwu ọdịiche dị na ọnụọgụ nke mgbasawanye ọkụ n'etiti graphite na nickel substrate30,38.
Ihe oyiyi AFM kwadoro na ihe nlele FS-NGF dị mma karịa ihe atụ BS-NGF (Njirimara SI1) (Figure SI2). Mgbọrọgwụ pụtara square (RMS) ụkpụrụ roughness nke FS-NGF/Ni (Fig. SI2c) na BS-NGF/Ni (Fig. SI2d) bụ 82 na 200 nm, n'otu n'otu (tụtara n'elu ebe 20 × 20 μm2). Enwere ike ịghọta isi ike dị elu dabere na nyocha elu nke foil nickel (NiAR) na steeti enwetara (ọgụgụ SI3). E gosiputara onyonyo SEM nke FS na BS-NiAR na eserese SI3a-d, na-egosipụta ụdị ọdịdị elu dị iche iche: foil FS-Ni a na-egbu maramara nwere nano- na micron-spherical spherical particles, ebe foil BS-Ni a na-edochaghị anya na-egosipụta ọkwa nrụpụta. dị ka ahụ nwere ike dị elu. na ida. E gosipụtara onyonyo dị ala na nke dị elu nke foil nickel annealed (NiA) na eserese SI3e–h. Na ọnụ ọgụgụ ndị a, anyị nwere ike ịhụ ọnụnọ nke ọtụtụ micron-sized nickel particles n'akụkụ abụọ nke nickel foil (Fig. SI3e-h). Nnukwu ọka nwere ike ịnwe ntụgharị ihu elu Ni(111), dịka akọwara 30,46 na mbụ. Enwere nnukwu ọdịiche dị na nickel foil morphology n'etiti FS-NiA na BS-NiA. Ihe siri ike dị elu nke BS-NGF/Ni bụ n'ihi elu nke BS-NiAR na-adịghị mma, nke elu ya na-anọgide na-adị njọ ọbụna mgbe ọ gbasasịrị (Figure SI3). Ụdị njirimara elu dị otú a tupu usoro uto na-enye ohere ka a na-achịkwa ike nke graphene na ihe nkiri graphite. Ọ ga-kwuru na mbụ mkpụrụ mere ụfọdụ ọka reorganization n'oge graphene ibu, nke dịtụ ibelata ọka size na dịtụ mụbara elu roughness nke mkpụrụ tụnyere annealed foil na catalyst film22.
Idozi nke ọma n'ịdị njọ elu nke mkpụrụ, oge na-akụda mmụọ (nha ọka) 30,47 na njikwa ntọhapụ43 ga-enyere aka belata nha nha NGF mpaghara na nha µm2 na/ma ọ bụ ọbụna nm2 (ya bụ, nha nha nke nanometer ole na ole). Iji chịkwaa nhụsianya elu nke mkpụrụ ahụ, a ga-atụle ụzọ ndị dị ka ihicha electrolytic nke foil nickel na-esi na ya pụta48. Enwere ike ịtinye foil nickel a na-emebu tupu ya emee na obere okpomọkụ (<900 °C) 46 na oge (<5 min) iji zere ịmepụta nnukwu ọka Ni (111) (nke bara uru maka uto FLG).
SLG na FLG graphene enweghị ike iguzogide esemokwu elu nke acid na mmiri, na-achọ ọkwa nkwado igwe n'oge usoro mbufe kemịkalụ mmiri mmiri22,34,38. N'adịghị ka nnyefe kemịkalụ mmiri nke polymer-akwado otu-layer graphene38, anyị chọpụtara na akụkụ abụọ nke NGF dị ka toro nwere ike ibufe na-enweghị nkwado polymer, dị ka egosiri na Figure 2a (lee Figure SI4a maka nkọwa ndị ọzọ). Nyefee NGF na mkpụrụ e nyere na-amalite site na itching mmiri nke ihe nkiri Ni30.49 dị n'okpuru. A na-etinye ihe atụ NGF/Ni/NGF toro eto n'otu abalị na 15 mL nke 70% HNO3 gbazere na 600 ml nke mmiri deionized (DI). Mgbe Ni foil gbazere kpamkpam, FS-NGF na-anọgide na-adị larịị ma na-ese n'elu mmiri mmiri, dị ka NGF / Ni / NGF sample, ebe BS-NGF na-emikpu n'ime mmiri (Fig. 2a, b). A na-ebufe NGF dịpụrụ adịpụ site n'otu beaker nwere mmiri dị ọhụrụ na beaker ọzọ ma sachaa NGF dịpụrụ adịpụ nke ọma, na-emegharị ugboro anọ ruo isii site na efere iko concave. N'ikpeazụ, FS-NGF na BS-NGF etinyere na mkpụrụ osisi achọrọ (Fig 2c).
Usoro mbufe kemịkalụ mmiri na-enweghị polymer maka NGF toro na foil nickel: (a) Usoro nhazi usoro (lee eserese SI4 maka nkọwa ndị ọzọ), (b) Foto dijitalụ nke NGF kewara ekewa mgbe Ni etching (2 samples), (c) Ihe atụ FS - na BS-NGF na-ebufe na mkpụrụ osisi SiO2 / Si, (d) FS-NGF na-ebufe na mkpụrụ osisi polymer opaque, (e) BS-NGF site na otu ihe atụ dị ka panel d (kewara n'ime akụkụ abụọ), na-ebufe ya na mpempe akwụkwọ C nke ọla edo. na Nafion (mkpụrụ osisi transperent na-agbanwe agbanwe, n'akụkụ akara na akụkụ uhie).
Rịba ama na mbufe SLG rụrụ site na iji usoro mbufe kemịkalụ mmiri chọrọ oge nhazi oge nke 20-24 awa 38. Site na usoro mbufe na-enweghị polymer gosipụtara ebe a (Ọnọdụ SI4a), oge nhazi NGF n'ozuzu na-ebelata nke ukwuu (ihe dị ka awa 15). Usoro ahụ gụnyere: (Nzọụkwụ 1) Kwadebe ngwọta etching ma tinye ihe nlele n'ime ya (~ nkeji 10), wee chere abalị maka Ni etching (~ 7200 nkeji), (Nzọụkwụ 2) Jiri mmiri na-ekpo ọkụ mee ihe (Nzọụkwụ - 3) . Chekwaa n'ime mmiri deionized ma ọ bụ bufee na mkpụrụ nke ebumnuche (nkeji 20). A na-ewepụ mmiri nke dị n'etiti NGF na nnukwu matriks site na capillary action (iji mpempe akwụkwọ) 38, mgbe ahụ, a na-ewepụ nsị mmiri ndị fọdụrụ site na ihicha eke (ihe dị ka 30 min), n'ikpeazụkwa, a na-ehichapụ ihe nlele ahụ maka 10 min. min na oven na-ekpo ọkụ (10-1 mbar) na 50-90 Celsius C (60 min) 38.
A maara graphite ka ọ na-eguzogide ọnụnọ mmiri na ikuku na oke okpomọkụ (≥ 200 Celsius) 50,51,52. Anyị nwalere ihe nlele site na iji Raman spectroscopy, SEM, na XRD mgbe nchekwa na mmiri deionized na ụlọ okpomọkụ na karama mechiri emechi maka ebe ọ bụla site na ụbọchị ole na ole ruo otu afọ (Nyocha SI4). Enweghị mbelata pụtara ìhè. Ọgụgụ 2c na-egosi FS-NGF na-akwụghị ụgwọ na BS-NGF na mmiri deionized. Anyị weghaara ha na mkpụrụ SiO2 (300 nm)/Si, dị ka egosiri na mmalite nke eserese 2c. Na mgbakwunye, dị ka egosiri na eserese 2d,e, enwere ike ibufe NGF na-aga n'ihu na ihe dị iche iche dị ka polymers (Thermabright polyamide sitere na Nexolve na Nafion) na akwụkwọ carbon nwere mkpuchi ọla edo. A na-etinye FS-NGF nke na-ese n'elu mmiri n'ụzọ dị mfe n'elu mkpụrụ akụ (Fig. 2c, d). Otú ọ dị, ihe atụ BS-NGF buru ibu karịa 3 cm2 siri ike ijikwa mgbe etinyere ya kpamkpam na mmiri. Na-emekarị, mgbe ha na-amalite ịtụgharị na mmiri, n'ihi na-akpachapụ anya njikwa mgbe ụfọdụ na-agbaji n'ime abụọ ma ọ bụ atọ akụkụ (Fig. 2e). N'ozuzu, anyị nwere ike nweta polymer-free nyefe nke PS- na BS-NGF (na-aga n'ihu na-enweghị nfefe na-enweghị NGF / Ni / NGF ibu na 6 cm2) maka samples ruo 6 na 3 cm2 na mpaghara, n'otu n'otu. Ihe ọ bụla fọdụrụ nnukwu ma ọ bụ obere iberibe nwere ike (dị mfe ịhụ na etching ngwọta ma ọ bụ deionized mmiri) na chọrọ mkpụrụ (~ 1 mm2, Figure SI4b, lee sample agafere na ọla kọpa grid dị ka na "FS-NGF: Ọdịdị na Njirimara (na-atụle) n'okpuru "Ụdị na Njirimara") ma ọ bụ chekwaa maka ojiji n'ọdịnihu (ọgụgụ SI4). Dabere na njirisi a, anyị na-eme atụmatụ na NGF nwere ike nwetaghachi na mkpụrụ nke ruru 98-99% (mgbe uto maka mbufe).
A na-enyocha ihe nlele mbufe na-enweghị polymer. Njirimara morphological nke dị n'elu enwetara na FS- na BS-NGF / SiO2 / Si (Fig 2c) na-eji anya microscopy (OM) na ihe oyiyi SEM (Fig. SI5 na Fig 3) gosiri na a na-ebufe ihe nlele ndị a na-enweghị microscopy. Mmebi ihe arụrụ arụ a na-ahụ anya dị ka mgbawa, oghere ma ọ bụ ebe akpọpụghị. Mpịakọta ndị dị na NGF na-eto eto (Fig 3b, d, nke akụ na-acha odo odo akara) nọgidere na-adịgide adịgide mgbe ebufechara. Ma FS- na BS-NGF bụ mpaghara FLG (mpaghara na-egbuke egbuke gosipụtara site na akụ na-acha anụnụ anụnụ na foto 3). N'ụzọ dị ịtụnanya, n'ụzọ dị iche na mpaghara ole na ole mebiri emebi a na-ahụkarị n'oge mbufe polymer nke ihe nkiri ultrathin graphite, ọtụtụ mpaghara FLG na MLG nke na-ejikọ na NGF (nke ejiri akụ na-acha anụnụ anụnụ akara na eserese 3d) ka ebufere n'enweghị mgbawa ma ọ bụ nkwụsịtụ (Nyocha 3d) . 3). . Ekwupụtakwara iguzosi ike n'ezi ihe n'ọrụ site na iji onyonyo TEM na SEM nke NGF bufee na grids ọla kọpa lace-carbon, dịka a tụlere ma emechaa ("FS-NGF: Structure and Properties"). BS-NGF / SiO2 / Si ebugharị dị njọ karịa FS-NGF / SiO2 / Si nwere ụkpụrụ rms nke 140 nm na 17 nm, n'otu n'otu, dị ka egosiri na Figure SI6a na b (20 × 20 μm2). Uru RMS nke NGF bufere na SiO2/Si substrate (RMS <2 nm) dị ala nke ukwuu (ihe dị ka ugboro 3) karịa nke NGF toro na Ni (Njirimara SI2), na-egosi na ike ike ọzọ nwere ike dabara na elu Ni. Tụkwasị na nke ahụ, ihe oyiyi AFM mere na nsọtụ nke FS- na BS-NGF / SiO2 / Si samples gosiri NGF ọkpụrụkpụ nke 100 na 80 nm, n'otu n'otu (Fig. SI7). Obere ọkpụrụkpụ nke BS-NGF nwere ike ịbụ n'ihi n'elu anaghị ekpughe ya ozugbo na gas na-ebu ụzọ.
Ebufere NGF (NiAG) na-enweghị polymer na SiO2 / Si wafer (lee Figure 2c): (a, b) ihe oyiyi SEM nke FS-NGF ebugharị: ịdị elu na ịdị elu (nke kwekọrọ na square oroma na panel). Ebe a na-ahụkarị) – a). (c, d) Ihe onyonyo SEM nke bufere BS-NGF: mmụba dị ala na nke dị elu (dakọtara na mpaghara a na-ahụkarị nke square oroma na panel c). (e, f) onyonyo AFM nke FS- na BS-NGF bufee. Akụ na-acha anụnụ anụnụ na-anọchi anya mpaghara FLG - ọdịiche na-egbuke egbuke, akụ cyan - ọdịiche MLG ojii, ụta uhie - ọdịiche ojii na-anọchite anya mpaghara NGF, akụ magenta na-anọchite anya mpịakọta.
A na-enyocha ihe mejupụtara kemịkalụ nke ndị toro na FS- na BS-NGF site na X-ray photoelectron spectroscopy (XPS) (Fig 4). A hụrụ ọnụ ọgụgụ kasị elu na-adịghị ike n'ụdị atụpụtara (Fig. 4a, b), kwekọrọ na Ni substrate (850 eV) nke FS- na BS-NGFs (NiAG) toro eto. Ọ dịghị ọnụ ọgụgụ kasị elu na ihe atụ nke FS- na BS-NGF / SiO2 / Si (Fig. 4c; egosighị ihe ndị yiri ya maka BS-NGF / SiO2 / Si), na-egosi na ọ dịghị ihe fọdụrụ Ni mmetọ mgbe ebufechara. . Ọnụọgụ 4d-f na-egosi ọkwa dị elu nke C 1 s, O 1 s na Si 2p ume ike nke FS-NGF/SiO2/Si. Ike njide nke C 1 s nke graphite bụ 284.4 eV53.54. A na-ewerekarị ọdịdị ahịrị elu nke graphite dị ka asymmetrical, dịka egosiri na foto 4d54. Ụdị dị elu nke isi ọkwa C 1 dị elu (Fig 4d) kwadoro nnyefe dị ọcha (ya bụ, ọ dịghị polymer residues), nke kwekọrọ na ọmụmụ gara aga38. Ogologo ahịrị nke C 1 s ụdịdị dị iche iche nke ụdị tolitere ọhụrụ (NiAG) na mgbe ebufechara bụ 0.55 na 0.62 eV, n'otu n'otu. Ụkpụrụ ndị a dị elu karịa nke SLG (0.49 eV maka SLG na mkpụrụ SiO2)38. Agbanyeghị, ụkpụrụ ndị a pere mpe karịa ogologo ahịrị akọwara na mbụ maka ihe atụ pyrolytic graphene gbadoro anya nke ukwuu (~ 0.75 eV) 53,54,55, na-egosi enweghị saịtị carbon nwere ntụpọ na ihe ugbu a. Ihe ngosi ọkwa ala C 1 s na O 1 enweghịkwa ubu, na-ewepụ mkpa maka deconvolution kacha elu54. Enwere elu satịlaịtị π → π* gburugburu 291.1 eV, nke a na-ahụkarị na ihe nlele graphite. Ihe nrịbama 103 eV na 532.5 eV dị na Si 2p na O 1 s isi larịị spectra (lee fig. 4e, f) ka etinyere na mkpụrụ SiO2 56, n'otu n'otu. XPS bụ usoro nke nwere mmetụta dị n'elu, yabụ akara ngosi kwekọrọ na Ni na SiO2 achọpụtara tupu na mgbe mbufe NGF gasịrị, n'otu n'otu, a na-eche na ọ sitere na mpaghara FLG. Ahụrụ nsonaazụ ndị yiri ya maka nlele BS-NGF bufee (egosighi ya).
Nsonaazụ NiAG XPS: (ac) Nyocha ụdịdị dị iche iche nke atọmịk elemental dị iche iche nke FS-NGF/Ni, BS-NGF/Ni tolitere wee bufee FS-NGF/SiO2/Si, otu. (d–f) Ihe ngosi dị elu nke ọkwa isi C 1 s, O 1s na Si 2p nke ihe atụ FS-NGF/SiO2/Si.
A na-enyocha ịdị mma nke kristal NGF a bufere site na iji X-ray diffraction (XRD). Ụdị XRD a na-ahụkarị (Fig. SI8) nke FS- na BS-NGF / SiO2 / Si na-egosi ọnụnọ nke mgbagwoju anya (0 0 0 2) na (0 0 0 4) na 26.6 ° na 54.7 °, yiri graphite. . Nke a na-akwado ogo kristal dị elu nke NGF ma kwekọọ na anya interlayer nke d = 0.335 nm, nke a na-edobe mgbe nzọụkwụ mbufe gasịrị. Ike nke elu diffraction (0 0 0 2) bụ ihe dị ka ugboro 30 nke ọnụ ọgụgụ kachasị elu (0 0 04), na-egosi na ụgbọ elu kristal NGF dabara nke ọma na elu nlele.
Dị ka nsonaazụ nke SEM, Raman spectroscopy, XPS na XRD si kwuo, ahụrụ àgwà BS-NGF/Ni ka ọ dị ka nke FS-NGF/Ni, ọ bụ ezie na ike rms ya dị ntakịrị elu (Njirimara SI2, SI5) na SI7).
SLG nwere akwa nkwado polymer ruo n'obosara 200 nm nwere ike ise n'elu mmiri. A na-ejikarị nhazi a na usoro mbufe kemịkalụ mmiri na-enyere aka polymer22,38. Graphene na graphite bụ hydrophobic (mmiri akụkụ 80-90 Celsius) 57 . A kọwo na ike nwere ike nke ma graphene na FLG dị larịị, nwere ike dị ala (~ 1 kJ / mol) maka mmegharị mmiri n'akụkụ elu58. Otú ọ dị, ike mkparịta ụka nke mmiri na graphene na atọ nke graphene dị ihe dịka - 13 na - 15 kJ / mol, 58 n'otu n'otu, na-egosi na mmekọrịta nke mmiri na NGF (ihe dị ka 300 layers) dị ala ma e jiri ya tụnyere graphene. Nke a nwere ike ịbụ otu n'ime ihe kpatara NGF nwere onwe ya ji anọgide na-adị larịị n'elu mmiri, ebe graphene na-enweghị onwe ya (nke na-ese n'elu mmiri) na-agbaji ma gbarie. Mgbe NGF na-emikpu kpamkpam na mmiri (nsonaazụ bụ otu maka NGF siri ike na nke dị larịị), akụkụ ya na-ehulata (Figure SI4). N'ihe banyere imikpu zuru oke, a na-atụ anya na ike mmekọrịta NGF-mmiri fọrọ nke nta ka ọ bụrụ okpukpu abụọ (tụnyere NGF na-ese n'elu mmiri) nakwa na nsọtụ nke NGF fold iji nọgide na-enwe njikọ dị elu (hydrophobicity). Anyị kwenyere na enwere ike ịmepụta atụmatụ iji zere ịchịkọta ọnụ nke NGF agbakwunyere. Otu ụzọ bụ iji ihe mgbaze gwakọtara megharịa mmeghachi omume wetting nke ihe nkiri graphite59.
Mbufe nke SLG na ụdị dị iche iche nke mkpụrụ site na usoro mbufe kemịkalụ mmiri ka akọpụtala mbụ. A na-anabatakarị na ndị agha van der Waals na-adịghị ike dị n'etiti ihe nkiri graphene / graphite na mkpụrụ (ma ọ bụrụ ihe ndị siri ike dị ka SiO2 / Si38,41,46,60, SiC38, Au42, Si pillars22 na lacy carbon films30, 34 ma ọ bụ ihe ndị na-agbanwe agbanwe). dị ka polyimide 37). N'ebe a, anyị na-eche na mmekọrịta nke otu ụdị na-achị. Anyị ahụghị mmebi ma ọ bụ peeling ọ bụla nke NGF maka ihe ọ bụla ewepụtara ebe a n'oge eji arụ ọrụ (n'oge njirimara n'okpuru oghere na / ma ọ bụ ọnọdụ ikuku ma ọ bụ n'oge nchekwa) (dịka ọmụmaatụ, Figure 2, SI7 na SI9). Na mgbakwunye, anyị ahụghị ọnụ ọgụgụ SiC na XPS C 1 s spectrum nke isi ọkwa nke NGF / SiO2 / Si sample (Fig 4). Nsonaazụ ndị a na-egosi na ọ nweghị njikọ kemịkalụ n'etiti NGF na mkpụrụ ebumnuche ebumnuche.
Na ngalaba gara aga, "Nfefe na-enweghị polymer nke FS- na BS-NGF," anyị gosipụtara na NGF nwere ike itolite ma nyefee n'akụkụ abụọ nke nickel foil. Ndị FS-NGF ndị a na BS-NGF abụghị otu n'ihe gbasara ịdị arọ nke elu, nke mere ka anyị nyochaa ngwa kachasị mma maka ụdị ọ bụla.
N'ịtụle nghọta na nro dị nro nke FS-NGF, anyị na-amụ usoro mpaghara ya, ngwa anya na eletriki n'ụzọ zuru ezu. Ihe owuwu na nhazi nke FS-NGF na-enweghị mbufe polymer bụ nke e ji njiri eletrọnịkị microscopy (TEM) eserese na nyocha ụkpụrụ mpaghara eletrọnịlụ (SAED). A na-egosipụta nsonaazụ kwekọrọ na foto 5. Ịmalite atụmatụ TEM dị ala gosipụtara ọnụnọ nke mpaghara NGF na FLG nwere àgwà ọdịiche dị iche iche nke electron, ya bụ ebe gbara ọchịchịrị na nke na-egbuke egbuke, n'otu n'otu (Fig 5a). Ihe nkiri ahụ n'ozuzu ya na-egosipụta ezi nguzosi ike n'ezi ihe na nkwụsi ike n'etiti mpaghara dị iche iche nke NGF na FLG, na-enwe ezigbo ndakọrịta na enweghị mmebi ma ọ bụ dọkasị, nke SEM (Njirimara 3) kwadoro na ọmụmụ TEM dị elu (Figure 5c-e). Karịsịa, na Fig. Ihe osise 5d na-egosi nhazi akwa akwa na akụkụ ya kachasị ukwuu (ọnọdụ nke akara akara ojii nwere akara na Figure 5d), bụ nke e ji ọdịdị triangular mara ma na-agụnye oyi akwa graphene na obosara nke ihe dịka 51. Ihe mejupụtara ya na oghere interplanar nke 0.33 ± 0.01 nm na-ebelata n'ọtụtụ ọkwa nke graphene na mpaghara kacha warara (njedebe nke akụ ojii siri ike na Figure 5 d).
Ihe onyonyo TEM Planar nke ihe nlele NiAG na-enweghị polymer na grid ọla kọpa carbon lacy: (a, b) onyonyo TEM dị ala gụnyere NGF na mpaghara FLG, (ce) onyonyo dị elu nke mpaghara dị iche iche na panel-a na panel-b bụ akụ akara nke otu agba. Akụ akwụkwọ ndụ akwụkwọ ndụ dị na paịlụ a na c na-egosi akụkụ okirikiri mebiri emebi n'oge nhazi osisi. (f–i) N'akụkụ a ruo c, a na-egosipụta ụkpụrụ SAED na mpaghara dị iche iche site na okirikiri anụnụ anụnụ, cyan, oroma na uhie, n'otu n'otu.
Nhazi rịbọn dị na eserese 5c na-egosi (nke ejiri akụ na-acha uhie uhie akara) ntụgharị kwụ ọtọ nke ụgbọ elu graphite lattice, nke nwere ike ịbụ n'ihi nhazi nke nanofolds n'akụkụ ihe nkiri ahụ (etinyere na Figure 5c) n'ihi oke nrụgide na-enweghị akwụ ụgwọ30,61,62 . N'okpuru TEM dị elu, nanofolds 30 ndị a na-egosipụta ntụgharị kristal dị iche iche karịa mpaghara NGF ndị ọzọ; Ụgbọ elu basal nke graphite lattice na-adabere na ya fọrọ nke nta ka ọ bụrụ kwụ ọtọ, kama ịbụ n'ahịrị dị ka ihe nkiri ndị ọzọ (tinyere na Figure 5c). N'otu aka ahụ, mpaghara FLG na-egosipụta oge ụfọdụ na eriri dị warara dị ka mpịachi dị warara (nke ejiri akụ na-acha anụnụ anụnụ akara), nke na-apụta na mmụba dị ala na nke ọkara na Figure 5b, 5e, n'otu n'otu. Ihe ntinye dị na eserese 5e na-akwado ọnụnọ nke okpukpu abụọ na atọ nke graphene n'ime mpaghara FLG (ntụgharị interplanar 0.33 ± 0.01 nm), nke dị mma na nkwekọrịta anyị gara aga30. Na mgbakwunye, ihe onyonyo SEM edekọtara nke NGF na-enweghị polymer bufere na grid ọla kọpa nwere ihe nkiri carbon lacy (mgbe emechara nha TEM n'elu) ka egosiri na eserese SI9. Mpaghara FLG kwụsịtụrụ nke ọma (nke ejiri ụta na-acha anụnụ anụnụ akara) yana mpaghara agbajiri agbaji na eserese SI9f. A na-ama ụma gosi akụ na-acha anụnụ anụnụ (na nsọtụ nke NGF ebugharị) iji gosipụta na mpaghara FLG nwere ike iguzogide usoro mbufe na-enweghị polymer. Na nchịkọta, onyogho ndị a na-akwado na NGF kwụsịtụrụ (gụnyere mpaghara FLG) na-ejigide iguzosi ike n'ezi ihe ọbụna mgbe ejiri ya na ikpughe na oghere dị elu n'oge nha TEM na SEM (Nyocha SI9).
N'ihi ọmarịcha larịị nke NGF (lee eserese 5a), ọ naghị esiri ike ịhazi flakes n'akụkụ axis ngalaba [0001] iji nyochaa usoro SAED. Dabere na ọkpụrụkpụ mpaghara nke ihe nkiri ahụ na ebe ọ nọ, a chọpụtara ọtụtụ mpaghara mmasị (isi 12) maka ọmụmụ ihe gbasara electron. N'ọgụgụ 5a–c, anọ n'ime mpaghara ndị a ka egosiri ma were okirikiri nwere agba (acha anụnụ anụnụ, cyan, oroma na uhie uhie). Ọgụgụ 2 na 3 maka ọnọdụ SAED. A na-enweta ọnụọgụ 5f na g site na mpaghara FLG nke egosiri na 5 na 5. Dị ka e gosiri na 5b na c, n'otu n'otu. Ha nwere usoro hexagonal yiri graphene gbagọrọ agbagọ63. Karịsịa, eserese 5f na-egosi ụkpụrụ atọ dị elu nwere otu nghazi nke mpaghara mpaghara [0001], na-atụgharị site na 10° na 20°, dị ka egosipụtara site na ndakọrịta n'akụkụ nke ụzọ atọ nke (10-10). N'otu aka ahụ, eserese 5g na-egosi ụkpụrụ hexagonal abụọ gbagoro agbagoro na 20º. Abụọ ma ọ bụ atọ dị iche iche nke hexagonal ụkpụrụ na FLG mpaghara nwere ike ibili site atọ in-ụgbọ elu ma ọ bụ nke ụgbọ elu graphene n'ígwé 33 na-atụgharị na ibe. N'ụzọ dị iche, usoro ngbanwe nke electron na Figure 5h,i (nke kwekọrọ na mpaghara NGF nke egosiri na eserese 5a) na-egosi otu ụkpụrụ [0001] nke nwere oke nhụsianya dị elu n'ozuzu ya, kwekọrọ na ọkpụrụkpụ ihe dị ukwuu. Ụdị SAED ndị a kwekọrọ na nhazi ihe osise dị arọ na ntụgharị etiti karịa FLG, dịka e si na index 64 pụta. Ịmara njirimara nke crystalline nke NGF gosipụtara ịdị n'otu nke abụọ ma ọ bụ atọ graphite (ma ọ bụ graphene) crystallites. Ihe dị ịrịba ama na mpaghara FLG bụ na kristal nwere ogo ụfọdụ n'ime ụgbọ elu ma ọ bụ n'èzí. Mpempe akwụkwọ eserese / oyi akwa nwere akụkụ ntụgharị n'ime ụgbọ elu nke 17°, 22° na 25° ka akọpụtala mbụ maka NGF toro na fim Ni 64. Ụkpụrụ ntụgharị ntụgharị a na-ahụ na ọmụmụ ihe a kwekọrọ na akụkụ ntụgharị a na-ahụbu (± 1 °) maka graphene BLG63 gbagọrọ agbagọ.
A tụrụ àgwà eletriki nke NGF / SiO2 / Si na 300 K karịa mpaghara 10 × 3 mm2. The ụkpụrụ nke electron ebu itinye uche, agagharị na conductivity bụ 1.6 × 1020 cm-3, 220 cm2 V-1 C-1 na 2000 S-cm-1, n'otu n'otu. Ụkpụrụ agagharị na ụkpụrụ omume nke NGF anyị yiri graphite eke2 ma dị elu karịa ahịa graphite pyrolytic dị elu (emepụtara na 3000 Celsius) 29. Ihe nlele eletrọn a na-ahụ anya bụ ụkpụrụ abụọ dị elu karịa nke a kọrọ na nso nso a (7.25 × 10 cm-3) maka ihe nkiri graphite micron-thick nke a kwadebere site na iji nnukwu okpomọkụ (3200 Celsius C) polyimide sheets 20 .
Anyị mekwara nha nnyefe a na-ahụ anya UV na FS-NGF bufere na mkpụrụ quartz (Foto 6). Ụdịdị dị iche iche na-egosi na ọ fọrọ nke nta ka ọ bụrụ nnyefe 62% na nso 350-800 nm, na-egosi na NGF bụ translucent na ìhè a na-ahụ anya. N'ezie, aha "KAUST" nwere ike ịhụ na foto dijitalụ nke ihe nlele na Figure 6b. Ọ bụ ezie na usoro nanocrystalline nke NGF dị iche na nke SLG, ọnụ ọgụgụ nke ọkwa nwere ike ime atụmatụ site na iji iwu nke 2.3% nnyefe ọnwụ kwa Layer65 ọzọ. Dị ka a mmekọrịta, ọnụ ọgụgụ nke graphene n'ígwé na 38% nnyefe ọnwụ bụ 21. The toro NGF tumadi mejupụtara 300 graphene n'ígwé, ie banyere 100 nm oké (Fig. 1, SI5 na SI7). Ya mere, anyị na-eche na nghọta anya anya a na-ahụ anya kwekọrọ na mpaghara FLG na MLG, ebe ọ bụ na a na-ekesa ha na fim ahụ (Figs 1, 3, 5 na 6c). Na mgbakwunye na data nhazi nke dị n'elu, conductivity na nghọta na-akwadokwa ogo kristal dị elu nke NGF bufee.
(a) Ntụnye nnyefe nke UV na-ahụ anya, (b) mbufe NGF na quartz na-eji ihe atụ nnọchite anya. (c) Nhazi nke NGF (igbe gbara ọchịchịrị) nke nwere mpaghara FLG na MLG ekesa nke ọma akara dị ka ụdị isi awọ n'oge nlele (lee eserese 1) (ihe dịka 0.1-3% mpaghara kwa 100 μm2). Ụdị enweghị usoro na nha ha dị na eserese ahụ bụ naanị maka ihe atụ, ọ bụghịkwa n'akụkụ ebe dị adị.
Translucent NGF toro site na CVD ebufefefefela ya na mbara silicon efu ma jiri ya na sel anyanwụ15,16. Ihe nrụpụta ike ngbanwe arụmọrụ (PCE) bụ 1.5%. Ndị NGF ndị a na-arụ ọrụ dị iche iche dị ka ọkwa nhazi na-arụ ọrụ, ụzọ ụgbọ njem na-akwụ ụgwọ, na electrodes transperent15,16. Otú ọ dị, ihe nkiri graphite abụghị otu. Nkwalite ọzọ dị mkpa site na iji nlezianya na-achịkwa nguzogide mpempe akwụkwọ na nnyefe anya nke electrode graphite, ebe ọ bụ na ihe abụọ a na-arụ ọrụ dị mkpa n'ịchọpụta uru PCE nke anyanwụ cell15,16. Dị ka ọ na-adịkarị, ihe nkiri graphene bụ 97.7% transperent na ìhè a na-ahụ anya, mana ha nwere nguzogide mpempe akwụkwọ nke 200-3000 ohms / sq.16. Enwere ike ibelata nguzogide elu nke ihe nkiri graphene site n'ịba ụba nke ọkwa (ọtụtụ nnyefe nke graphene layers) na doping na HNO3 (~ 30 Ohm / sq.) 66. Otú ọ dị, usoro a na-ewe ogologo oge ma dị iche iche na-ebufe n'ígwé adịghị anọgide na-enwe ezi kọntaktị mgbe niile. Anyị n'ihu n'akụkụ NGF nwere Njirimara dị ka conductivity 2000 S / cm, film mgbochi 50 ohm / sq. na 62% nghọta, na-eme ka ọ bụrụ ihe ọzọ dị mma maka ọwa ndị na-eduzi ma ọ bụ electrodes na-arụ ọrụ na sel anyanwụ15,16.
Ọ bụ ezie na nhazi na kemịkalụ elu nke BS-NGF yiri FS-NGF, ike ya dị iche ("Uto nke FS- na BS-NGF"). Na mbụ, anyị na-eji ultra-thin film graphite22 dị ka ihe mmetụta gas. Ya mere, anyị nwalere ike nke iji BS-NGF maka ọrụ nhụta gas (Figure SI10). Nke mbụ, a bufere akụkụ mm2 nke BS-NGF na mgbawa ihe mmetụta electrode interdigitating (Ọnyocha SI10a-c). Nkọwapụta nrụpụta nke mgbawa ka akọọrọ mbụ; Mpaghara mmetụta ya na-arụ ọrụ bụ 9 mm267. N'ihe onyonyo SEM (Ọnyocha SI10b na c), a na-ahụ electrode ọla edo dị n'okpuru nke ọma site na NGF. Ọzọ, enwere ike ịhụ na enwetara mkpuchi mgbawa otu maka nlele niile. A na-edekọ nha ihe mmetụta gas nke gas dị iche iche (Fig. SI10d) (Fig SI11) na ọnụego nzaghachi na-esi na ya pụta gosipụtara na fig. SI10g. O yikarịrị ka ikuku ndị ọzọ na-etinye aka gụnyere SO2 (200 ppm), H2 (2%), CH4 (200 ppm), CO2 (2%), H2S (200 ppm) na NH3 (200 ppm). Otu ihe kpatara ya bụ NO2. ọdịdị electrophilic nke gas22,68. Mgbe adsorbed n'elu graphene, ọ na-ebelata nnabata nke electrons ugbu a site na usoro. Ntụnyere oge nzaghachi data nke BS-NGF sensọ nwere ihe mmetụta e bipụtara na mbụ ka ewepụtara na tebụl SI2. Usoro maka ịmegharị ihe mmetụta NGF site na iji plasma UV, plasma O3 ma ọ bụ thermal (50-150 ° C) ọgwụgwọ nke ihe nlele ekpughere na-aga n'ihu, nke ọma na-esote mmejuputa usoro agbakwunyere69.
N'oge usoro CVD, uto graphene na-apụta n'akụkụ abụọ nke ihe na-akpata ihe41. Agbanyeghị, a na-achụpụ BS-graphene n'oge usoro mbufe41. N'ime ọmụmụ ihe a, anyị na-egosi na ọganihu NGF dị elu na nnyefe NGF na-enweghị polymer nwere ike nweta n'akụkụ abụọ nke nkwado nkwado. BS-NGF dị gịrịgịrị (~ 80 nm) karịa FS-NGF (~ 100 nm), a na-akọwakwa ọdịiche a site n'eziokwu ahụ bụ na BS-Ni anaghị ekpughe ya ozugbo na ikuku gas na-ebu ụzọ. Anyị chọpụtakwara na ike nke NiAR substrate na-emetụta ike nke NGF. Nsonaazụ ndị a na-egosi na enwere ike iji FS-NGF planar toro dị ka ihe mbụ maka graphene (site na exfoliation method70) ma ọ bụ dị ka ọwa na-eduzi na sel anyanwụ15,16. N'ụzọ dị iche, a ga-eji BS-NGF mee ihe maka nchọpụta gas (Fig SI9) na ikekwe maka usoro nchekwa nchekwa ike71,72 ebe ọdịdị elu ya ga-aba uru.
N'ịtụle ihe ndị dị n'elu, ọ bara uru ijikọta ọrụ ugbu a na ihe nkiri graphite bipụtara na mbụ nke CVD toro na iji nickel foil. Dị ka a na-ahụ na Tebụl 2, nrụgide dị elu anyị ji mee ihe na-ebelata oge mmeghachi omume (ogbo uto) ọbụna na obere okpomọkụ (na nso 850-1300 Celsius). Anyị nwetakwara uto ka ukwuu karịa ka ọ na-adịbu, na-egosi ike ịgbasawanye. E nwere ihe ndị ọzọ a ga-atụle, ụfọdụ n'ime ha abanyela na tebụl.
NGF dị elu nwere akụkụ abụọ toro na foil nickel site na CVD catalytic. Site n'iwepụ ihe ndị na-emepụta polymer omenala (dị ka ndị a na-eji na CVD graphene), anyị na-enweta nnyefe mmiri dị ọcha na enweghị ntụpọ nke NGF (nke na-etolite n'azụ na n'ihu nke nickel foil) na usoro dị iche iche dị mkpa. N'ụzọ doro anya, NGF gụnyere mpaghara FLG na MLG (nke na-abụkarị 0.1% ruo 3% kwa 100 µm2) bụ nke etinyere nke ọma n'ime ihe nkiri siri ike. Planar TEM na-egosi na mpaghara ndị a nwere ngwugwu graphite/graphene abụọ ma ọ bụ atọ (crystals ma ọ bụ n'ígwé, n'otu n'otu), ụfọdụ n'ime ha nwere ndakọrịta ntụgharị nke 10–20°. Mpaghara FLG na MLG na-ahụ maka nghọta nke FS-NGF na ìhè a na-ahụ anya. Banyere mpempe akwụkwọ n'azụ, enwere ike iburu ha na mpempe akwụkwọ n'ihu ma, dị ka egosiri, nwere ike inwe nzube ọrụ (dịka ọmụmaatụ, maka nchọpụta gas). Ọmụmụ ihe ndị a bara uru nke ukwuu maka ibelata mkpofu na ọnụ ahịa n'ọtụtụ ụlọ ọrụ CVD.
N'ozuzu, nkezi ọkpụrụkpụ nke CVD NGF dị n'etiti (obere na multi-layer) graphene na ụlọ ọrụ mmepụta ihe (micrometer) graphite. Ihe dị iche iche nke ihe onwunwe ha na-adọrọ mmasị, jikọtara ya na usoro dị mfe anyị mepụtara maka mmepụta na njem ha, na-eme ka ihe nkiri ndị a dị mma maka ngwa ndị chọrọ nzaghachi ọrụ nke graphite, na-enweghị ego nke usoro mmepụta mmepụta ihe na-arụ ọrụ ike ugbu a.
Awụnyere foil nickel dị 25-μm (99.5% ịdị ọcha, Goodfellow) na igwe mkpuchi CVD azụmahịa (Aixtron 4-inch BMPro). A na-ehichapụ usoro ahụ na argon ma wepụ ya na nrụgide isi nke 10-3 mbar. Mgbe ahụ, a na-etinye nickel foil. na Ar / H2 (Mgbe tupu anneal Ni foil maka 5 min, a na-ekpuchi foil na nrụgide nke 500 mbar na 900 Celsius C. NGF na-etinye na ntinye nke CH4 / H2 (100 cm3 ọ bụla) maka 5 min. A na-eme ka ihe nlele ahụ dị jụụ na okpomọkụ n'okpuru 700 Celsius C site na iji Ar flow (4000 cm3) na 40 Celsius C / min nkọwa na njikarịcha nke usoro uto NGF na-akọwa n'ebe ọzọ30.
A na-ahụ anya ọdịdị elu nke ihe nlele ahụ site na SEM site na iji microscope Zeiss Merlin (1 kV, 50 pA). A na-eji AFM (Dimension Icon SPM, Bruker) tụọ ihe nlele elu na nha NGF. A na-eme nha TEM na SAED site na iji microscope FEI Titan 80-300 Cubed nke nwere egbe ọkụ dị elu (300 kV), ụdị FEI Wien monochromator na onye na-ahụ maka oghere ihu igwe CEOS iji nweta nsonaazụ ikpeazụ. Mkpebi oghere 0.09 nm. Ebufere ihe nlele NGF na grid ọla kọpa nwere mkpuchi carbon lacy maka onyonyo TEM dị larịị yana nyocha nhazi usoro SAED. Ya mere, ọtụtụ n'ime ihe atụ nke flocs na-akwụsịtụ na pores nke akpụkpọ ahụ na-akwado. XRD tụlere ihe nlele NGF ebufere. A na-enweta usoro mgbasa ozi X-ray site na iji diffractometer ntụ ntụ (Brucker, D2 phase shifter with Cu Kα source, 1.5418 Å na LYNXEYE detector) site na iji isi iyi radieshon Cu nwere oghere ntụpọ nke 3 mm.
Edekọbara ọtụtụ ihe nlere Raman site na iji microscope confocal na-ejikọta (Alpha 300 RA, WITEC). Ejiri laser 532 nm nwere ike mkpali dị ala (25%) iji zere mmetụta ndị na-ebute ọkụ. A na-eme X-ray photoelectron spectroscopy (XPS) na Kratos Axis Ultra spectrometer n'elu ebe nlele nke 300 × 700 μm2 na-eji monochromatic Al Kα radieshon (hν = 1486.6 eV) na ike nke 150 W. Mkpebi spectrometer nwetara na ike nnyefe nke 160 eV na 20 eV, n'otu n'otu. A na-egbutu ihe nlele NGF na-ebufe na SiO2 n'ime iberibe (3 × 10 mm2 ọ bụla) na-eji PLS6MW (1.06 μm) ytterbium fiber laser na 30 W. A na-emepụta kọntaktị waya ọla kọpa (50 μm gbara ọkpụrụkpụ) site na iji mado ọlaọcha n'okpuru microscope anya. Emere njem eletriki na nnwale mmetụta Ụlọ Nzukọ na ihe atụ ndị a na 300 K na mgbanwe ndọta nke ± 9 Tesla na usoro nha nke anụ ahụ (PPMS EverCool-II, Quantum Design, USA). Edekọbara UV-vis spectra site na iji Lambda 950 UV-vis spectrophotometer na oke 350-800 nm NGF bufere na substrates quartz na ihe nlele quartz.
Ekenyere ihe mmetụta nguzogide kemịkalụ (mgbawa electrode interdigitated) na bọọdụ sekit a na-ebipụta omenala 73 ma wepụta nguzogide ahụ nwa oge. A na-ejikọta bọọdụ sekit e biri ebi nke ngwaọrụ ahụ dị na kọntaktị kọntaktị ma tinye ya n'ime ụlọ gas gas 74. A na-ewere nha ndị na-eguzogide na voltaji nke 1 V na nyocha na-aga n'ihu site na ihicha na ikpughe gas wee kpochaa ọzọ. A na-ehicha ụlọ ahụ na mbụ site na iji nitrogen na-asachapụ na 200 cm3 maka awa 1 iji hụ na mwepụ nke nyocha ndị ọzọ niile dị na ụlọ ahụ, gụnyere mmiri mmiri. A na-ewepụta ndị nyocha nke ọ bụla n'otu n'otu wee jiri nwayọọ nwayọọ banye n'ime ụlọ ahụ n'otu nha nha nke 200 cm3 site na imechi cylinder N2.
Ebipụtala ụdị akụkọ a edegharịrị ma nwee ike ịnweta ya site na njikọ dị n'elu akụkọ ahụ.
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