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Fina-finan graphite na Nanoscale (NGFs) sune nanomaterials masu ƙarfi waɗanda za'a iya samar da su ta hanyar haɓakar tururin sinadarai, amma tambayoyi sun kasance game da sauƙin canja wuri da yadda ilimin halittar jiki ke shafar amfani da su a cikin na'urori masu zuwa. Anan mun bayar da rahoton ci gaban NGF a bangarorin biyu na foil polycrystalline nickel (yankin 55 cm2, kauri game da 100 nm) da canja wurin da ba shi da polymer (gaba da baya, yanki har zuwa 6 cm2). Saboda ilimin halittar jiki na foil mai kara kuzari, fina-finan carbon guda biyu sun bambanta da halayensu na zahiri da sauran halayensu (kamar rashin ƙarfi). Mun nuna cewa NGFs tare da rougher backside sun dace da ganewar NO2, yayin da NGFs masu laushi da kuma masu gudanarwa a gefen gaba (2000 S / cm, juriya na takarda - 50 ohms / m2) na iya zama masu jagoranci. tashar ko electrode na tantanin halitta na hasken rana (tunda yana watsa 62% na haske mai gani). Gabaɗaya, haɓakar da aka kwatanta da tafiyar matakai na iya taimakawa fahimtar NGF azaman madadin abu na carbon don aikace-aikacen fasaha inda graphene da micron-thick graphite films basu dace ba.
Graphite abu ne na masana'antu da ake amfani da shi sosai. Musamman ma, graphite yana da kaddarorin ƙananan ƙarancin yawa da kuma babban yanayin zafi a cikin jirgin sama da lantarki, kuma yana da ƙarfi sosai a cikin yanayin zafi da sinadarai1,2. Flake graphite sanannen kayan farawa ne don binciken graphene3. Lokacin da aka sarrafa shi zuwa fina-finai na bakin ciki, ana iya amfani da shi a cikin aikace-aikace da yawa, gami da magudanar zafi don na'urorin lantarki kamar wayowin komai da ruwan 4,5,6,7, azaman abu mai aiki a cikin na'urori masu auna firikwensin8,9,10 kuma don kariyar kutse na lantarki11. 12 da fina-finai don lithography a cikin matsananci ultraviolet13,14, gudanar da tashoshi a cikin hasken rana sel15,16. Ga duk waɗannan aikace-aikacen, zai zama babban fa'ida idan manyan wuraren fina-finai na graphite (NGFs) tare da kauri da aka sarrafa a cikin nanoscale <100 nm za a iya samarwa da jigilar su cikin sauƙi.
Ana shirya fina-finan graphite ta hanyoyi daban-daban. A cikin wani yanayi, haɗawa da haɓakawa da haɓakawa ana amfani da su don samar da flakes na graphene10,11,17. Dole ne a ƙara sarrafa flakes ɗin zuwa fina-finai na kauri da ake buƙata, kuma sau da yawa yana ɗaukar kwanaki da yawa don samar da zanen zane mai yawa. Wata hanya kuma ita ce farawa da ƙwararrun maƙamai masu zayyana. A cikin masana'antu, zanen gado na polymers suna carbonized (a 1000-1500 ° C) sannan kuma a graphitized (a 2800-3200 ° C) don samar da kayan da aka tsara da kyau. Ko da yake ingancin waɗannan fina-finai yana da girma, yawan amfani da makamashi yana da mahimmanci1,18,19 kuma ƙananan kauri yana iyakance ga ƙananan microns1,18,19,20.
Catalytic sinadaran tururi jijiya (CVD) sanannen hanya ce don samar da fina-finai na graphene da ultrathin graphite (<10 nm) tare da ingantaccen tsari da tsada mai tsada21,22,23,24,25,26,27. Koyaya, idan aka kwatanta da haɓakar fina-finai na graphene da ultrathin graphite28, girman yanki mai girma da/ko aikace-aikacen NGF ta amfani da CVD ko da ƙarancin bincike ne11,13,29,30,31,32,33.
CVD-girma graphene da graphite fina-finai sau da yawa suna buƙatar canjawa wuri zuwa abubuwan aiki34. Waɗannan ɓangarorin fina-finai na bakin ciki sun haɗa da manyan hanyoyi guda biyu35: (1) Canja wurin ba tare da etch36,37 da (2) Canja wurin sinadarai na tushen etch (an goyan bayan substrate)14,34,38. Kowace hanya tana da wasu fa'idodi da rashin amfani kuma dole ne a zaɓa dangane da aikace-aikacen da aka yi niyya, kamar yadda aka bayyana a wani wuri35,39. Don fina-finai graphene/graphite da aka girma akan abubuwan haɓakawa, canja wuri ta hanyar tsarin sinadarai mai jika (wanda polymethyl methacrylate (PMMA) shine mafi yawan amfani da layin tallafi) ya kasance zaɓi na farko13,30,34,38,40,41,42. Ka et al. An ambaci cewa ba a yi amfani da polymer don canja wurin NGF (samfurin girman kusan 4 cm2) 25,43, amma ba a ba da cikakkun bayanai game da kwanciyar hankali da / ko kulawa a lokacin canja wuri ba; Rike tsarin sunadarai ta amfani da polymers sun ƙunshi matakai da yawa, gami da aikace-aikace da cirewar Layer polymer na hadaya30,38,40,41,42. Wannan tsari yana da rashin amfani: alal misali, ragowar polymer na iya canza kaddarorin girma film38. Ƙarin aiki zai iya cire ragowar polymer, amma waɗannan ƙarin matakan ƙara farashi da lokacin samar da fim38,40. A lokacin ci gaban CVD, ana ajiye wani Layer na graphene ba kawai a gefen gaba na foil mai haɓaka ba (gefen da ke fuskantar kwararar tururi), har ma a gefen baya. Koyaya, ana ɗaukar ƙarshen a matsayin sharar gida kuma ana iya cire shi da sauri ta plasma mai laushi38,41. Sake yin amfani da wannan fim zai iya taimakawa wajen haɓaka yawan amfanin ƙasa, koda kuwa yana da ƙarancin inganci fiye da fuskar fim ɗin carbon.
Anan, muna ba da rahoton shirye-shiryen ci gaban bifacial na wafer-sikelin NGF tare da ingantaccen tsarin tsari akan foil polycrystalline nickel ta CVD. An yi la'akari da yadda rashin ƙarfi na gaba da baya na foil ya shafi ilimin halittar jiki da tsarin NGF. Har ila yau, muna nuna NGF-free-free-polymer-friendly canja wuri daga bangarorin biyu na nickel foil a kan multifunctional substrates da kuma nuna yadda fina-finai na gaba da baya suka dace da aikace-aikace daban-daban.
Sassan da ke biyowa suna tattauna kauri daban-daban na fim ɗin graphite dangane da adadin madaidaicin graphene: (i) graphene Layer Layer guda (SLG, 1 Layer), (ii) ƴan ƙaramin graphene Layer (FLG, <10 layers), (iii) graphene multilayer ( MLG, 10-30 yadudduka) da (iv) NGF (~ 300 yadudduka). Na karshen shine mafi yawan kauri da aka bayyana azaman kashi na yanki (kimanin yanki 97% a cikin 100 µm2)30. Shi ya sa ake kiran fim ɗin gabaɗaya NGF.
Polycrystalline nickel foils da aka yi amfani da su don haɗar graphene da fina-finan graphite suna da nau'i daban-daban a sakamakon yin su da kuma sarrafa su. Kwanan nan mun ba da rahoton wani binciken don inganta tsarin ci gaban NGF30. Mun nuna cewa sigogi na tsari irin su annealing lokaci da kuma matsa lamba a cikin ɗakin girma a lokacin girma yana taka muhimmiyar rawa wajen samun NGFs na kauri mai kauri. Anan, mun kara bincikar ci gaban NGF akan gaba mai gogewa (FS) da baya (BS) saman bangon nickel (Fig. 1a). An bincika nau'ikan samfurori guda uku FS da BS, waɗanda aka jera a cikin Tebura 1. Bayan dubawa na gani, ana iya ganin haɓakar haɓakar NGF a ɓangarorin biyu na foil nickel (NiAG) ta canjin launi na babban nau'in Ni daga nau'in azurfa mai ƙima. launin toka zuwa launin toka mai launin toka (Fig. 1a); An tabbatar da ma'aunin microscopic (Fig. 1b, c). Wani nau'in bakan Raman na FS-NGF da aka gani a cikin yanki mai haske kuma ana nuna su ta kiban ja, blue da orange a cikin Hoto 1b a cikin Hoto 1c. Halayen Raman kololuwar graphite G (1683 cm-1) da 2D (2696 cm-1) sun tabbatar da haɓakar NGF crystalline sosai (Fig. 1c, Table SI1). A cikin fim ɗin, an lura da fifikon ra'ayi na Raman tare da rabo mai ƙarfi (I2D/IG) ~ 0.3, yayin da Raman spectra tare da I2D/IG = 0.8 ba a cika gani ba. Rashin ƙarancin kololuwa (D = 1350 cm-1) a cikin duka fim ɗin yana nuna babban ingancin ci gaban NGF. An sami irin wannan sakamakon Raman akan samfurin BS-NGF (Hoto SI1 a da b, Table SI1).
Kwatanta NiAG FS- da BS-NGF: (a) Hoton samfurin NGF (NiAG) na yau da kullun yana nuna haɓakar NGF a ma'aunin wafer (55 cm2) da sakamakon BS- da FS-Ni samfuran foil, (b) FS-NGF Hotuna / Ni da aka samu ta hanyar na'urar gani na gani, (c) faifan Raman na yau da kullun da aka rubuta a wurare daban-daban a cikin panel b, (d, f) Hotunan SEM a girma daban-daban akan FS-NGF/Ni, (e, g) Hotunan SEM a girma daban-daban Saita BS -NGF/Ni. Kibiya mai shuɗi tana nuna yankin FLG, kibiyar lemu tana nuna yankin MLG (kusa da yankin FLG), kibiyar ja tana nuna yankin NGF, kibiya magenta tana nuna ninka.
Tun da girma ya dogara da kauri na farko substrate, crystal size, fuskantarwa, da kuma hatsi iyakoki, cimma m iko na NGF kauri a kan manyan yankunan ya kasance kalubale20,34,44. Wannan binciken yayi amfani da abun ciki da muka buga a baya30. Wannan tsari yana samar da yanki mai haske na 0.1 zuwa 3% a kowace 100 µm230. A cikin sassan da ke gaba, muna gabatar da sakamako na yankuna biyu. Hotunan SEM masu girma suna nuna kasancewar wurare masu yawa masu haske a bangarorin biyu (Fig. 1f, g), yana nuna kasancewar yankunan FLG da MLG30,45. Hakanan an tabbatar da wannan ta hanyar rarrabawar Raman (Fig. 1c) da sakamakon TEM (an tattauna daga baya a cikin sashin "FS-NGF: tsari da kaddarorin"). Yankunan FLG da MLG da aka lura akan samfuran FS- da BS-NGF/Ni (na gaba da baya NGF da aka girma akan Ni) na iya girma akan manyan hatsin Ni (111) da aka kafa a lokacin pre-annealing22,30,45. An lura da nadawa a bangarorin biyu (Fig. 1b, alama da kibiyoyi masu launin shuɗi). Ana samun waɗannan folds sau da yawa a cikin CVD-girma graphene da graphite fina-finai saboda babban bambanci a cikin coefficient na thermal fadadawa tsakanin graphite da nickel substrate30,38.
Hoton AFM ya tabbatar da cewa samfurin FS-NGF ya fi dacewa fiye da samfurin BS-NGF (Figure SI1) (Figure SI2). Tushen ma'anar murabba'i (RMS) ƙimar ƙimar FS-NGF / Ni (Fig. SI2c) da BS-NGF / Ni (Fig. SI2d) sune 82 da 200 nm, bi da bi (ana auna kan yanki na 20 × ku 20m2). Za'a iya fahimtar mafi girman rashin ƙarfi dangane da binciken saman nickel (NiAR) a cikin yanayin da aka karɓa (Hoto SI3). Hotunan SEM na FS da BS-NiAR ana nuna su a cikin Figures SI3a-d, suna nuna nau'ikan halittu daban-daban: gogewar FS-Ni foil yana da nano- da micron-sized spherical particles, yayin da foil na BS-Ni mara goge yana nuna matakan samarwa. a matsayin barbashi tare da babban ƙarfi. da raguwa. Hotuna masu ƙanƙanta da babban ƙuduri na foil ɗin nickel (NiA) an nuna su a cikin Hoto SI3e–h. A cikin waɗannan ƙididdiga, zamu iya lura da kasancewar ƙwayoyin nickel masu girma da yawa a bangarorin biyu na nickel foil (Fig. SI3e-h). Manyan hatsi na iya samun daidaitawar Ni(111), kamar yadda aka ruwaito a baya30,46. Akwai manyan bambance-bambance a cikin ilimin halittar nickel foil tsakanin FS-NiA da BS-NiA. Mafi girman rashin ƙarfi na BS-NGF/Ni shine saboda yanayin da ba a goge ba na BS-NiAR, wanda samansa ya kasance mai tsananin ƙanƙara koda bayan annealing (Hoto SI3). Irin wannan nau'i na yanayin yanayin kafin tsarin girma yana ba da damar sarrafa ƙarancin graphene da graphite fina-finai. Ya kamata a lura da cewa asali substrate an yi wasu gyaran hatsi a lokacin girma na graphene, wanda dan kadan ya rage girman ƙwayar hatsi kuma ya ɗan ƙara girman yanayin ƙasa idan aka kwatanta da foil da aka rufe da kuma mai kara kuzari film22.
Kyakkyawan daidaita yanayin yanayin ƙasa, lokacin ɓata lokaci (girman hatsi) 30,47 da ikon saki43 zai taimaka rage daidaituwar kauri na yanki na NGF zuwa ma'aunin µm2 da/ko ma nm2 (watau bambancin kauri na ƴan nanometers). Don sarrafa yanayin ƙasa na substrate, hanyoyin kamar electrolytic polishing na sakamakon nickel foil za a iya la'akari48. The pretreated nickel foil sa'an nan za a iya annealed a ƙananan zafin jiki (<900 °C) 46 da kuma lokaci (< 5 min) don kauce wa samuwar manyan Ni (111) hatsi (wanda yake da amfani ga FLG girma).
SLG da FLG graphene ba su iya jure yanayin tashin hankali na acid da ruwa, suna buƙatar yadudduka na goyan bayan injina yayin aiwatar da canjin sinadarai22,34,38. Ya bambanta da canja wurin sinadarai mai jika na graphene38 mai goyon bayan polymer guda ɗaya, mun gano cewa za a iya canja wurin ɓangarorin biyu na NGF mai girma ba tare da tallafin polymer ba, kamar yadda aka nuna a cikin Hoto 2a (duba Hoto SI4a don ƙarin cikakkun bayanai). Canja wurin NGF zuwa abin da aka bayar yana farawa da rigar etching na fim ɗin Ni30.49 na asali. An sanya samfuran NGF/Ni/NGF da aka girma cikin dare a cikin 15 ml na 70% HNO3 da aka diluted tare da 600 ml na ruwa mai deionized (DI). Bayan Ni foil ya narkar da gaba daya, FS-NGF ya kasance mai lebur kuma yana shawagi a saman ruwan, kamar samfurin NGF/Ni/NGF, yayin da BS-NGF ke nutsewa cikin ruwa (Fig. 2a,b). Daga nan sai aka canja wurin NGF ɗin da ke keɓe daga wani baƙar da ke ɗauke da ruwan da ba a so ba zuwa wani biki kuma an wanke NGF ɗin da ke keɓe sosai, ana maimaita sau huɗu zuwa shida ta cikin kwanon gilashin. A ƙarshe, an sanya FS-NGF da BS-NGF akan abin da ake so (Fig. 2c).
Tsarin canja wurin sinadarai mara-polymer don NGF wanda aka girma akan foil nickel: (a) Tsarin tafiyar da tsari (duba Hoto SI4 don ƙarin cikakkun bayanai), (b) Hoton dijital na NGF da aka rabu bayan Ni etching (samfuran 2), (c) Misali FS - da kuma BS-NGF canja wuri zuwa SiO2 / Si substrate, (d) FS-NGF canja wuri zuwa opaque polymer substrate, (e) BS-NGF daga wannan samfurin kamar panel d (kasu kashi biyu sassa), canjawa wuri zuwa zinariya plated C takarda. da Nafion (m substrate m, gefuna alama da ja sasanninta).
Lura cewa canja wurin SLG da aka yi ta amfani da hanyoyin canja wurin sinadarai mai jika yana buƙatar jimlar lokacin aiki na 20-24 hours 38 . Tare da fasahar canja wuri mara amfani da polymer wanda aka nuna anan (Hoto SI4a), gabaɗayan lokacin canja wurin NGF yana raguwa sosai (kimanin sa'o'i 15). Tsarin ya ƙunshi: (Mataki na 1) Shirya maganin etching kuma sanya samfurin a ciki (~ mintoci 10), sannan ku jira dare don Ni etching (~ 7200 minutes), (Mataki na 2) Rinse da ruwa mai narkewa (Mataki - 3) . Ajiye a cikin ruwan da aka lalatar ko canja wuri zuwa wuri mai niyya (minti 20). Ruwan da aka makale tsakanin NGF da matrix mai girma ana cire shi ta hanyar aikin capillary (ta amfani da takarda mai gogewa) 38, sannan ana cire sauran ɗigon ruwa ta bushewar yanayi (kimanin 30 min), kuma a ƙarshe samfurin ya bushe don 10 min. min a cikin tanda (10-1mbar) a 50-90 ° C (minti 60) 38.
An san Graphite don jure kasancewar ruwa da iska a yanayin zafi mai kyau (≥ 200 ° C) 50,51,52. Mun gwada samfurori ta amfani da Raman spectroscopy, SEM, da XRD bayan ajiya a cikin ruwa mai tsabta a dakin da zafin jiki da kuma a cikin kwalabe da aka rufe don ko'ina daga 'yan kwanaki zuwa shekara guda (Figure SI4). Babu ɓatawar gani. Hoto na 2c yana nuna FS-NGF masu kyauta da BS-NGF a cikin ruwa mai lalata. Mun kama su akan SiO2 (300 nm)/Si substrate, kamar yadda aka nuna a farkon Hoto 2c. Bugu da ƙari, kamar yadda aka nuna a cikin Hoto 2d, e, ana iya canja wurin ci gaba da NGF zuwa wasu sassa daban-daban kamar su polymers (Thermabright polyamide daga Nexolve da Nafion) da kuma takarda carbon mai rufin zinariya. An sanya FS-NGF mai iyo a cikin sauƙi a kan maƙasudin manufa (Fig. 2c, d). Duk da haka, samfuran BS-NGF da suka fi girma fiye da 3 cm2 sun kasance masu wuyar sarrafawa lokacin da aka nutsar da su cikin ruwa gaba ɗaya. Yawancin lokaci, idan sun fara mirgina a cikin ruwa, saboda rashin kulawa, wani lokaci suna karya kashi biyu ko uku (Fig. 2e). Gabaɗaya, mun sami damar cimma canja wurin kyauta na polymer na PS- da BS-NGF (ci gaba da canja wuri maras kyau ba tare da ci gaban NGF / Ni / NGF a 6 cm2) don samfuran har zuwa 6 da 3 cm2 a cikin yanki, bi da bi. Duk wani sauran manyan ko ƙananan guda za a iya (sauƙaƙin gani a cikin maganin etching ko ruwan da aka lalata) akan abin da ake so (~ 1 mm2, Figure SI4b, duba samfurin da aka canjawa wuri zuwa grid na jan karfe kamar yadda a cikin "FS-NGF: Tsarin da Kaddarorin (an tattauna) karkashin "Tsarin da Kaddarorin") ko adana don amfanin gaba (Hoto SI4). Bisa ga wannan ma'auni, mun kiyasta cewa za a iya dawo da NGF a cikin yawan amfanin ƙasa har zuwa 98-99% (bayan girma don canja wuri).
An yi nazarin samfuran canja wuri ba tare da polymer ba dalla-dalla. Halin yanayin yanayin yanayin da aka samu akan FS- da BS-NGF / SiO2 / Si (Fig. 2c) ta amfani da microscopy na gani (OM) da hotuna SEM (Fig. SI5 da Fig. 3) sun nuna cewa an canja waɗannan samfurori ba tare da microscopy ba. Lalacewar tsarin da ake iya gani kamar tsagewa, ramuka, ko wuraren da ba a birgewa ba. Rubuce-rubucen da ke kan NGF mai girma (Fig. 3b, d, masu alamar kibiyoyi masu launin shuɗi) sun kasance daidai bayan canja wuri. Dukansu FS- da BS-NGFs sun ƙunshi yankuna na FLG (yankuna masu haske waɗanda aka nuna ta kiban shuɗi a cikin Hoto 3). Abin mamaki, ya bambanta da ƴan yankuna da suka lalace galibi ana lura dasu yayin canja wurin polymer na fina-finai na ultrathin, yankuna FLG da MLG da yawa da ke da alaƙa da NGF (alama da kibiyoyi masu shuɗi a cikin Hoto 3d) an canza su ba tare da fasa ko karya ba (Hoto 3d) . 3). . An ƙara tabbatar da amincin injina ta amfani da hotunan TEM da SEM na NGF da aka tura su zuwa grid ɗin jan ƙarfe na yadin da aka saka, kamar yadda aka tattauna daga baya ("FS-NGF: Tsarin da Kaddarorin"). BS-NGF / SiO2 / Si da aka canjawa wuri ya fi FS-NGF / SiO2 / Si tare da ƙimar rms na 140 nm da 17 nm, bi da bi, kamar yadda aka nuna a Figure SI6a da b (20 × 20 μm2). Ƙimar RMS na NGF da aka canjawa wuri zuwa SiO2/Si substrate (RMS <2 nm) ya ragu sosai (kimanin sau 3) fiye da na NGF da aka girma akan Ni (Figure SI2), yana nuna cewa ƙarin rashin ƙarfi na iya dacewa da Ni surface . Bugu da ƙari, Hotunan AFM da aka yi a gefuna na FS- da BS-NGF / SiO2 / Si samfurori sun nuna nauyin NGF na 100 da 80 nm, bi da bi (Fig. SI7). Karamin kauri na BS-NGF na iya zama sakamakon saman ba a fallasa kai tsaye ga iskar gas na farko.
Canja wurin NGF (NiAG) ba tare da polymer akan SiO2 / Si wafer (duba Hoto 2c): (a,b) Hotunan SEM na FS-NGF da aka canjawa wuri: ƙananan girma da girma (daidai da square orange a cikin panel). Wurare na yau da kullun) - a). (c, d) Hotunan SEM na BS-NGF da aka canjawa wuri: ƙananan girma da girma (daidai da yanayin da aka nuna ta wurin orange square a cikin panel c). (e, f) Hotunan AFM na FS- da BS-NGFs da aka canjawa wuri. Kibiya mai launin shuɗi tana wakiltar yankin FLG - bambanci mai haske, kibiya cyan - bambancin MLG baki, kibiya ja - bambancin baki yana wakiltar yankin NGF, kibiya magenta tana wakiltar ninka.
Abubuwan sinadaran da aka girma da kuma canjawa wuri FS- da BS-NGFs an bincikar su ta hanyar X-ray photoelectron spectroscopy (XPS) (Fig. 4). An lura da kololuwar rauni a cikin ma'aunin da aka auna (Fig. 4a, b), wanda ya dace da Ni (850 eV) na girma FS- da BS-NGFs (NiAG). Babu kololuwa a cikin sikelin da aka auna na canjawa wuri FS- da BS-NGF/SiO2/Si (Fig. 4c; ba a nuna irin wannan sakamako na BS-NGF/SiO2/Si), yana nuna cewa babu sauran gurɓatawar Ni bayan canja wuri. . Figures 4d-f suna nuna babban ƙuduri na C 1 s, O 1 s da Si 2p matakan makamashi na FS-NGF / SiO2 / Si. Ƙarfin dauri na C 1 s na graphite shine 284.4 eV53.54. Siffar madaidaiciyar kololuwar graphite ana ɗaukarta azaman asymmetrical, kamar yadda aka nuna a hoto 4d54. Babban madaidaicin madaidaicin matakin C 1 s bakan (Fig. 4d) kuma ya tabbatar da canja wuri mai tsabta (watau babu ragowar polymer), wanda ya dace da karatun baya38. Matsakaicin layin C 1 s na samfurin sabon girma (NiAG) da kuma bayan canja wuri sune 0.55 da 0.62 eV, bi da bi. Waɗannan dabi'u sun fi na SLG (0.49 eV don SLG akan siginar SiO2)38. Koyaya, waɗannan ƙimar sun fi ƙasa da faɗin layin da aka bayar a baya don samfuran pyrolytic graphene masu dacewa sosai (~ 0.75 eV) 53,54,55, yana nuna rashin ƙarancin rukunin carbon a cikin kayan na yanzu. Siffofin matakin matakin C 1 s da O 1 suma basu da kafadu, suna kawar da buƙatu don ƙaƙƙarfan ƙaƙƙarfan ƙaƙƙarfan ƙazanta54. Akwai kololuwar tauraron tauraron dan adam π → π* a kusa da 291.1 eV, wanda galibi ana gani a cikin samfuran graphite. Siginonin 103 eV da 532.5 eV a cikin siginar Si 2p da O 1 s core matakin bakan (duba siffa 4e, f) ana danganta su zuwa ga SiO2 56 substrate, bi da bi. XPS wata fasaha ce mai hankali, don haka siginonin da suka dace da Ni da SiO2 da aka gano kafin da bayan canja wurin NGF, bi da bi, ana ɗauka sun samo asali ne daga yankin FLG. An lura da irin wannan sakamakon don samfuran BS-NGF da aka canjawa wuri (ba a nuna ba).
Sakamakon NiAG XPS: (ac) Binciken nau'ikan nau'ikan atomic daban-daban na girma FS-NGF/Ni, BS-NGF/Ni da canja wurin FS-NGF/SiO2/Si, bi da bi. (d-f) Maɗaukaki mai mahimmanci na matakan mahimmanci C 1 s, O 1s da Si 2p na samfurin FS-NGF / SiO2 / Si.
An tantance gabaɗayan ingancin lu'ulu'u na NGF da aka canjawa wuri ta amfani da diffraction X-ray (XRD). Hanyoyin XRD na al'ada (Fig. SI8) na canjawa wuri FS- da BS-NGF / SiO2 / Si suna nuna kasancewar kololuwar diffraction (0 0 0 2) da (0 0 0 4) a 26.6 ° da 54.7 °, kama da graphite. . Wannan yana tabbatar da ingancin kristal mai girma na NGF kuma yayi daidai da nisa tsakanin interlayer na d = 0.335 nm, wanda aka kiyaye bayan matakin canja wuri. Ƙarfin ƙwanƙwasa kololuwa (0 0 0 2) kusan sau 30 ne na ƙwanƙolin ɓarna (0 0 0 4), yana nuna cewa jirgin saman kristal na NGF ya yi daidai da saman samfurin.
Dangane da sakamakon SEM, Raman spectroscopy, XPS da XRD, an gano ingancin BS-NGF/Ni daidai yake da na FS-NGF/Ni, kodayake rashin ƙarfi na rms ya ɗan fi girma (Figures SI2, SI5) da SI7).
SLGs tare da yaduddukan tallafi na polymer har zuwa kauri 200 nm suna iya iyo akan ruwa. Ana amfani da wannan saitin galibi a cikin hanyoyin canja wurin sinadarai da ke taimakon polymer22,38. Graphene da graphite sune hydrophobic (rigar kusurwa 80-90 °) 57 . An ba da rahoton yuwuwar filayen makamashi na graphene da FLG suna da ɗan lebur, tare da ƙarancin ƙarfin kuzari (~ 1 kJ/mol) don motsin ruwa na gefe58. Duk da haka, ƙarfin hulɗar da aka ƙididdigewa na ruwa tare da graphene da nau'i uku na graphene kusan - 13 da - 15 kJ / mol, 58 bi da bi, yana nuna cewa hulɗar ruwa tare da NGF (kimanin 300 layers) ya ragu idan aka kwatanta da graphene. Wannan na iya zama ɗaya daga cikin dalilan da ya sa NGF mai ɗorewa ya kasance a kwance a saman ruwa, yayin da graphene mai ɗorewa (wanda ke yawo a cikin ruwa) yana murƙushewa ya rushe. Lokacin da aka nutsar da NGF gaba ɗaya cikin ruwa (sakamakon iri ɗaya ne ga NGF mai laushi da lebur), gefunansa suna lanƙwasa (Hoto SI4). A cikin yanayin cikakken nutsewa, ana sa ran cewa makamashin hulɗar ruwa na NGF ya kusan ninka sau biyu (idan aka kwatanta da NGF mai iyo) kuma cewa gefuna na NGF ninka don kula da babban kusurwar lamba (hydrophobicity). Mun yi imanin cewa za a iya samar da dabaru don guje wa karkatar da gefuna na NGFs da aka saka. Hanya ɗaya ita ce a yi amfani da gauraye masu kaushi don daidaita yanayin jika na fim ɗin graphite59.
Canja wurin SLG zuwa nau'ikan ma'auni daban-daban ta hanyar hanyoyin canja wurin sinadarai a baya an ba da rahoton. An yarda da shi gabaɗaya cewa sojojin van der Waals masu rauni suna wanzuwa tsakanin fina-finai na graphene / graphite da substrates (kasance masu tsattsauran ra'ayi kamar SiO2/Si38,41,46,60, SiC38, Au42, Si pillars22 da lacy carbon films30, 34 ko masu sassauƙa. kamar polyimide 37). Anan muna ɗauka cewa hulɗar nau'ikan iri ɗaya ta fi rinjaye. Ba mu lura da wani lalacewa ko kwasfa na NGF ba don kowane ɗayan abubuwan da aka gabatar a nan yayin sarrafa injina (lokacin da aka keɓancewa a ƙarƙashin vacuum da/ko yanayin yanayi ko lokacin ajiya) (misali, Hoto 2, SI7 da SI9). Bugu da ƙari, ba mu lura da ƙimar SiC ba a cikin XPS C 1 s bakan na ainihin matakin NGF / SiO2 / Si samfurin (Fig. 4). Waɗannan sakamakon suna nuna cewa babu haɗin sinadarai tsakanin NGF da maƙasudin manufa.
A cikin sashin da ya gabata, " Canja wurin kyauta na Polymer na FS- da BS-NGF," mun nuna cewa NGF na iya girma da canja wuri a bangarorin biyu na nickel foil. Waɗannan FS-NGFs da BS-NGFs ba daidai ba ne dangane da ƙaƙƙarfan yanayi, wanda ya sa mu bincika mafi dacewa aikace-aikacen kowane nau'in.
Idan aka yi la'akari da bayyananniyar sarari da santsi na FS-NGF, mun yi nazarin tsarin gida, kayan gani da kayan lantarki daki-daki. Tsarin da tsarin FS-NGF ba tare da canja wurin polymer ba an kwatanta su ta hanyar siginar microscopy na lantarki (TEM) da kuma zaɓaɓɓen yanki na lantarki (SAED) nazarin ƙirar ƙira. Ana nuna sakamakon da ya dace a cikin Hoto 5. Ƙananan girman girman girman shirin TEM ya nuna kasancewar yankunan NGF da FLG tare da nau'o'in bambancin electron, watau wurare masu duhu da haske, bi da bi (Fig. 5a). Fim ɗin gabaɗaya yana nuna kyakkyawan ingancin injiniya da kwanciyar hankali tsakanin yankuna daban-daban na NGF da FLG, tare da haɓaka mai kyau kuma babu lalacewa ko tsagewa, wanda kuma SEM (Hoto 3) ya tabbatar da shi da kuma karatun TEM mai girma (Figure 5c-e). Musamman, a cikin Hoto na 5d yana nuna tsarin gada a mafi girman sashi (matsayin da aka yi alama da kibiya mai dige-dige a cikin Hoto 5d), wanda ke da siffar triangular kuma ya ƙunshi Layer graphene tare da nisa na kusan 51. Abun da ke ciki tare da tazarar interplanar na 0.33 ± 0.01 nm yana ƙara raguwa zuwa yawancin yadudduka na graphene a cikin yanki mafi ƙanƙanta (ƙarshen ƙaƙƙarfan kibiya mai ƙarfi a cikin Hoto 5 d).
Hoton Planar TEM na samfurin NiAG mai kyauta na polymer akan grid lacy tagulla: (a, b) Hotunan TEM masu ƙarancin girma ciki har da yankunan NGF da FLG, (ce) Hotuna masu girma na yankuna daban-daban a cikin panel-a da panel-b sune kibiyoyi masu alamar launi iri ɗaya. Koren kibiyoyi a cikin bangarori a da c suna nuna wuraren da'irar lalacewa yayin daidaita katako. (f–i) A cikin bangarori a zuwa c, ƙirar SAED a yankuna daban-daban ana nuna su ta shuɗi, cyan, orange, da da'ira ja, bi da bi.
Tsarin kintinkiri a cikin Hoto 5c yana nuna (alama tare da kibiya ja) madaidaiciyar daidaitawar jiragen sama na graphite, wanda zai iya zama saboda samuwar nanofolds tare da fim ɗin (saka a cikin Hoto 5c) saboda wuce gona da iri mara nauyi mai ƙarfi30,61,62 . A ƙarƙashin babban ƙudurin TEM, waɗannan nanofolds 30 suna nuna madaidaicin crystallographic daban-daban fiye da sauran yankin NGF; jiragen saman basal na graphite lattice suna daidaitawa kusan a tsaye, maimakon a kwance kamar sauran fim ɗin (sake cikin hoto na 5c). Hakazalika, yankin FLG lokaci-lokaci yana baje kolin layi-layi da kunkuntar folds-kamar folds (alama da kiban shuɗi), waɗanda ke bayyana a ƙarami da matsakaicin girma a cikin Figures 5b, 5e, bi da bi. Shigarwa a cikin Hoto 5e yana tabbatar da kasancewar yadudduka na graphene guda biyu da uku a cikin sashin FLG (nisa tsakanin 0.33 ± 0.01 nm), wanda ke da kyakkyawar yarjejeniya tare da sakamakonmu na baya30. Bugu da ƙari, faifan SEM da aka yi rikodin na NGF-kyauta na polymer waɗanda aka canjawa wuri zuwa grid tagulla tare da fina-finai na lacy carbon (bayan yin ma'aunin TEM na sama) ana nunawa a cikin Hoto SI9. Yankin FLG da aka dakatar da rijiyar (mai alama da kibiya mai shuɗi) da yankin da ya karye a cikin Hoto SI9f. An gabatar da kibiya mai launin shuɗi (a gefen NGF da aka canjawa wuri) da gangan don nuna cewa yankin FLG zai iya tsayayya da tsarin canja wuri ba tare da polymer ba. A taƙaice, waɗannan hotuna sun tabbatar da cewa NGF da aka dakatar da shi (ciki har da yankin FLG) yana kiyaye amincin injina ko da bayan kulawa mai ƙarfi da fallasa zuwa babban injin yayin ma'aunin TEM da SEM (Figure SI9).
Saboda kyakkyawan shimfidar NGF (duba Hoto 5a), ba shi da wahala a daidaita flakes tare da yankin yanki [0001] don nazarin tsarin SAED. Dangane da kauri na gida na fim ɗin da wurinsa, an gano yankuna da yawa na sha'awa (maki 12) don nazarin rarrabuwar wutar lantarki. A cikin Figures 5a-c, huɗu daga cikin waɗannan yankuna na yau da kullun ana nuna su kuma an yi musu alama da da'irori masu launi (blue, cyan, orange, and ja codeed). Hoto na 2 da 3 don yanayin SAED. An samo hotuna 5f da g daga yankin FLG da aka nuna a cikin Figures 5 da 5. Kamar yadda aka nuna a Figures 5b da c, bi da bi. Suna da tsarin hexagonal mai kama da murɗaɗɗen graphene63. Musamman, Hoto na 5f yana nuna sifofi guda uku da aka ɗora tare da daidaitawa iri ɗaya na axis [0001], wanda aka juya ta 10° da 20°, kamar yadda aka tabbatar ta rashin daidaituwar angular na nau'i-nau'i uku na (10-10). Hakazalika, Hoto na 5g yana nuna sifofi guda biyu masu girman kai da aka juya da 20°. Rukuni biyu ko uku na sifofin hexagonal a cikin yankin FLG na iya tasowa daga cikin jirgin sama ko daga cikin jirgin saman graphene yadudduka 33 sun juya dangi da juna. Sabanin haka, tsarin rarrabuwar wutar lantarki a cikin Hoto 5h,i (daidai da yankin NGF da aka nuna a cikin Hoto 5a) yana nuna tsarin [0001] guda ɗaya tare da babban ƙarfin rarrabuwar ma'ana gabaɗaya, daidai da kauri mafi girma. Waɗannan samfuran SAED sun dace da tsarin zane mai kauri da matsakaicin matsakaici fiye da FLG, kamar yadda aka fayyace daga ma'aunin 64. Halayen kaddarorin crystalline na NGF ya bayyana kasancewar haɗin gwiwar graphite (ko graphene) crystallites biyu ko uku. Abin da ya fi dacewa a cikin yankin FLG shine cewa crystallites suna da ƙayyadaddun ƙayyadaddun fahimta a cikin jirgin sama ko daga cikin jirgin. A baya an ba da rahoton barbashi/yadudduka na graphite tare da kusurwoyin jujjuyawa a cikin jirgin sama na 17°, 22° da 25° a baya don NGF da aka girma akan finafinan Ni 64. Ƙimar kusurwar jujjuyawar da aka lura a cikin wannan binciken sun yi daidai da kusurwar jujjuyawar da aka gani a baya (± 1 °) don murƙushe BLG63 graphene.
An auna kayan lantarki na NGF / SiO2 / Si a 300 K akan yanki na 10 × 3 mm2. Ma'auni na electron dillalai taro, motsi da kuma conductivity ne 1.6 × 1020 cm-3, 220 cm2 V-1 C-1 da 2000 S-cm-1, bi da bi. Motsi da halayen halayen mu na NGF sun yi kama da graphite2 na halitta kuma sun fi girma fiye da kasuwancin da ake samu mai ma'amala da pyrolytic graphite (wanda aka samar a 3000 °C)29. Abubuwan da aka lura da ƙimar haɓaka mai ɗaukar lantarki sune umarni biyu na girma sama da waɗanda aka ruwaito kwanan nan (7.25 × 10 cm-3) don finafinan graphite mai kauri da aka shirya ta amfani da babban zafin jiki (3200 ° C) polyimide zanen gado 20 .
Mun kuma yi ma'aunin watsawa na UV akan FS-NGF da aka canjawa wuri zuwa ma'auni na ma'adini (Hoto 6). Sakamakon bakan yana nuna kusan 62% a cikin kewayon 350-800 nm, yana nuna cewa NGF yana jujjuyawa zuwa haske mai gani. A gaskiya ma, ana iya ganin sunan "KAUST" a cikin hoton dijital na samfurin a cikin Hoto 6b. Kodayake tsarin nanocrystalline na NGF ya bambanta da na SLG, ana iya ƙididdige adadin yawan yadudduka ta amfani da ka'idar asarar watsawa ta 2.3% a kowane ƙarin Layer65. Bisa ga wannan dangantaka, adadin graphene yadudduka tare da 38% asarar watsawa shine 21. NGF mai girma ya ƙunshi 300 graphene layers, watau game da 100 nm lokacin farin ciki (Fig. 1, SI5 da SI7). Sabili da haka, muna ɗauka cewa bayanin da aka gani na gani ya dace da yankunan FLG da MLG, tun da an rarraba su a cikin fim din (Figs. 1, 3, 5 da 6c). Baya ga bayanan tsarin da ke sama, aiki da gaskiya kuma sun tabbatar da ingancin kristal mai girma na NGF da aka canjawa wuri.
(a) Ma'aunin watsawa na UV, (b) Canja wurin NGF na yau da kullun akan ma'adini ta amfani da samfurin wakilci. (c) Tsarin tsari na NGF (akwatin duhu) tare da yankuna FLG da MLG da aka rarraba a ko'ina a matsayin sifofi masu launin toka a cikin samfurin (duba Hoto 1) (kimanin 0.1-3% yanki na 100 μm2). Siffofin bazuwar da girmansu a cikin zane don dalilai ne kawai kuma basu dace da ainihin wuraren ba.
Translucent NGF wanda CVD ya girma a baya an canza shi zuwa saman siliki maras tushe kuma ana amfani dashi a cikin sel na hasken rana15,16. Sakamakon ingantaccen canjin wutar lantarki (PCE) shine 1.5%. Waɗannan NGFs suna yin ayyuka da yawa kamar yadudduka masu aiki, cajin hanyoyin sufuri, da na'urorin lantarki na gaskiya15,16. Duk da haka, fim din graphite ba daidai ba ne. Ƙarin haɓakawa ya zama dole ta hanyar kula da juriya na takarda a hankali da watsawar gani na lantarki na graphite, tun da waɗannan kaddarorin biyu suna taka muhimmiyar rawa wajen ƙayyade ƙimar PCE na hasken rana15,16. Yawanci, graphene fina-finai ne 97.7% m ga bayyane haske, amma da takardar juriya na 200-3000 ohms/sq.16. Za'a iya rage juriya na fina-finai na graphene ta hanyar ƙara yawan adadin yadudduka (canja wuri da yawa na graphene layers) da doping tare da HNO3 (~ 30 Ohm / sq.) 66. Koyaya, wannan tsari yana ɗaukar lokaci mai tsawo kuma nau'ikan canja wuri daban-daban ba koyaushe suna kula da kyakkyawar lamba ba. Mu gaba gefen NGF yana da kaddarorin kamar conductivity 2000 S / cm, film juriya 50 ohm / sq. da 62% nuna gaskiya, wanda ya sa ya zama madaidaicin madadin don tashoshi masu sarrafawa ko na'urorin lantarki a cikin sel na hasken rana15,16.
Ko da yake tsari da sinadarai na BS-NGF sun yi kama da FS-NGF, rashin girman sa ya bambanta ("Growth of FS- da BS-NGF"). A baya can, mun yi amfani da ultra-bakin ciki fim graphite22 a matsayin gas firikwensin. Don haka, mun gwada yuwuwar amfani da BS-NGF don ayyukan gano iskar gas (Hoto SI10). Da farko, an tura sassan BS-NGF masu girman mm2 zuwa guntu firikwensin lantarki mai tsaka-tsaki (Hoto SI10a-c). An ba da rahoton bayanan masana'anta na guntu a baya; yankin sa mai aiki shine 9 mm267. A cikin Hotunan SEM (Hoto SI10b da c), wutar lantarkin da ke ƙarƙashin gwal tana bayyane ta hanyar NGF. Bugu da ƙari, ana iya ganin cewa an sami ɗaukar nauyin guntu iri ɗaya don duk samfuran. An rubuta ma'auni na firikwensin gas na iskar gas daban-daban (Fig. SI10d) (Fig. SI11) kuma an nuna sakamakon sakamakon sakamako a cikin Fig. SI10g. Mai yiwuwa tare da sauran iskar gas masu shiga ciki ciki har da SO2 (200 ppm), H2 (2%), CH4 (200 ppm), CO2 (2%), H2S (200 ppm) da NH3 (200 ppm). Dalili ɗaya mai yiwuwa shine NO2. yanayin electrophilic na gas22,68. Lokacin adsorbed a saman graphene, yana rage yawan sha da tsarin na yanzu. Kwatanta bayanan lokacin amsawa na firikwensin BS-NGF tare da firikwensin da aka buga a baya an gabatar da su a cikin Table SI2. Hanyar sake kunna na'urori masu auna firikwensin NGF ta amfani da plasma UV, plasma O3 ko thermal (50-150 ° C) jiyya na samfurori da aka fallasa yana gudana, wanda ya dace da aiwatar da tsarin da aka saka69.
A yayin aiwatar da CVD, haɓakar graphene yana faruwa a ɓangarorin biyu na mai kara kuzari41. Koyaya, BS-graphene yawanci ana fitar dashi yayin aikin canja wuri41. A cikin wannan binciken, mun nuna cewa babban ingancin NGF girma da kuma polymer-free NGF canja wuri za a iya samu a bangarorin biyu na goyon bayan mai kara kuzari. BS-NGF ya fi bakin ciki (~ 80 nm) fiye da FS-NGF (~ 100 nm), kuma an bayyana wannan bambanci ta gaskiyar cewa BS-Ni ba a bayyana kai tsaye ga madaidaicin iskar gas ba. Mun kuma gano cewa rashin ƙarfi na NiAR substrate yana rinjayar rashin ƙarfi na NGF. Wadannan sakamakon sun nuna cewa FS-NGF mai girma na iya amfani da shi azaman kayan haɓaka don graphene (ta hanyar exfoliation70) ko azaman tashar gudanarwa a cikin ƙwayoyin rana15,16. Sabanin haka, BS-NGF za a yi amfani da shi don gano iskar gas (Fig. SI9) kuma mai yiwuwa don tsarin ajiyar makamashi71,72 inda yanayin yanayinsa zai kasance da amfani.
Idan akai la'akari da abin da ke sama, yana da amfani don haɗa aikin na yanzu tare da fina-finan graphite da aka buga a baya wanda CVD ya girma da kuma amfani da foil nickel. Kamar yadda ake iya gani a cikin Tebura 2, matsi mafi girma da muka yi amfani da su sun rage lokacin amsawa (matakin girma) ko da a ƙananan yanayin zafi (a cikin kewayon 850-1300 ° C). Mun kuma sami girma fiye da yadda aka saba, yana nuna yuwuwar haɓakawa. Akwai wasu abubuwan da za a yi la'akari da su, wasu daga cikinsu mun haɗa su a cikin tebur.
NGF mai inganci mai gefe biyu an girma akan foil nickel ta CVD catalytic. Ta hanyar kawar da na'urorin polymer na gargajiya (kamar waɗanda aka yi amfani da su a cikin CVD graphene), muna samun tsabtataccen canja wurin rigar mara lahani na NGF (wanda aka girma a baya da gaban gaba na nickel foil) zuwa nau'i-nau'i masu mahimmanci na tsari. Musamman, NGF ya haɗa da yankunan FLG da MLG (yawanci 0.1% zuwa 3% a kowace 100 µm2) waɗanda aka haɗa su da kyau a cikin fim mai kauri. Planar TEM yana nuna cewa waɗannan yankuna sun ƙunshi tararrabi biyu zuwa uku na graphite/graphene (crystals ko yadudduka, bi da bi), wasu daga cikinsu suna da rashin daidaituwar juyi na 10-20°. Yankunan FLG da MLG suna da alhakin bayyana gaskiyar FS-NGF zuwa haske mai gani. Amma ga zanen gado na baya, ana iya ɗaukar su a layi daya zuwa zanen gado na gaba kuma, kamar yadda aka nuna, suna iya samun maƙasudin aiki (misali, gano gas). Waɗannan karatun suna da fa'ida sosai don rage sharar gida da farashi a cikin ma'aunin CPD na masana'antu.
Gabaɗaya, matsakaicin kauri na CVD NGF ya ta'allaka ne tsakanin (ƙananan- da Multi-Layer) graphene da masana'antu (micrometer) zanen zanen hoto. Matsakaicin kaddarorin su masu ban sha'awa, haɗe tare da hanya mai sauƙi da muka haɓaka don samarwa da jigilar su, ya sa waɗannan fina-finai sun dace da aikace-aikacen da ke buƙatar amsawar aikin graphite, ba tare da kashe hanyoyin samar da masana'antu masu ƙarfi da ƙarfi a halin yanzu ba.
An shigar da foil na nickel mai kauri 25-μm (99.5% tsafta, Goodfellow) a cikin injin CVD na kasuwanci (Aixtron 4-inch BMPro). An wanke tsarin tare da argon kuma an kwashe shi zuwa matsa lamba na 10-3 mbar. Sa'an nan kuma an sanya foil nickel. a cikin Ar / H2 (Bayan pre-annealing Ni foil don 5 min, an fallasa foil ɗin zuwa matsa lamba na 500 mbar a 900 ° C. NGF an ajiye shi a cikin kwararar CH4 / H2 (100 cm3 kowanne) don 5 min. Sa'an nan kuma an sanyaya samfurin zuwa zafin jiki a ƙasa da 700 ° C ta amfani da kwararar Ar (4000 cm3) a 40 ° C / min cikakkun bayanai game da inganta tsarin ci gaban NGF a wani wuri30.
Siffar yanayin halittar samfurin SEM ta hango ta ta amfani da na'urar duban ganimar Zeiss Merlin (1 kV, 50 pA). An auna nauyin samfurin samfurin da kauri na NGF ta amfani da AFM (Dimension Icon SPM, Bruker). Anyi amfani da ma'aunin TEM da SAED ta amfani da microscope na FEI Titan 80-300 Cubed sanye take da babban bindiga mai fitar da fili mai haske (300kV), nau'in FEI Wien monochromator da mai gyara yanayin ruwan tabarau na CEOS don samun sakamako na ƙarshe. ƙudurin sarari 0.09 nm. An canza samfuran NGF zuwa grid ɗin tagulla mai rufi na carbon lacy don hoton TEM mai lebur da nazarin tsarin SAED. Don haka, yawancin flocs samfurin an dakatar da su a cikin ramuka na membrane mai tallafi. An yi nazarin samfuran NGF da aka canjawa wuri ta XRD. An samo nau'i-nau'i na X-ray ta amfani da diffractometer foda (Brucker, D2 lokaci shifter tare da Cu Kα source, 1.5418 Å da LYNXEYE mai ganowa) ta amfani da tushen radiation Cu tare da diamita na katako na 3 mm.
An yi rikodin ma'aunin ma'aunin Raman da yawa ta amfani da na'urar haɗe-haɗe (Alpha 300 RA, WITEC). An yi amfani da Laser 532nm tare da ƙananan ƙarfin motsa jiki (25%) don guje wa tasirin zafi. X-ray photoelectron spectroscopy (XPS) da aka yi a kan wani Kratos Axis Ultra spectrometer a kan samfurin yanki na 300 × 700 μm2 ta amfani da monochromatic Al Kα radiation (hν = 1486.6 eV) a wani iko na 150 W. Resolution bakan da aka samu a karfin watsawa na 160 eV da 20 eV, bi da bi. NGF samfurori da aka canjawa wuri zuwa SiO2 an yanke su cikin guda (3 × 10 mm2 kowanne) ta amfani da PLS6MW (1.06 μm) ytterbium fiber Laser a 30 W. Copper waya lambobin sadarwa (50 μm lokacin farin ciki) an ƙirƙira ta amfani da manna na azurfa a ƙarƙashin wani microscope na gani. An gudanar da jigilar jigilar lantarki da gwaje-gwajen tasirin Hall akan waɗannan samfurori a 300 K da bambancin filin maganadisu na ± 9 Tesla a cikin tsarin ma'auni na jiki (PPMS EverCool-II, Quantum Design, Amurka). An yi rikodin bakan UV-vis da aka watsa ta amfani da Lambda 950 UV-vis spectrophotometer a cikin kewayon 350-800 nm NGF da aka canjawa wuri zuwa ma'auni na ma'adini da samfurori na ma'adini.
An haɗa firikwensin juriya na sinadarai ( guntu mai tsaka-tsakin lantarki) zuwa allon da'irar bugu na al'ada 73 kuma an fitar da juriya cikin ɗan lokaci. Kwamfutar da'irar da aka buga wanda na'urar take a kai an haɗa shi da tashoshi na lamba kuma an sanya shi a cikin ɗakin jin iskar gas 74. An ɗauki ma'aunin juriya a ƙarfin lantarki na 1 V tare da ci gaba da dubawa daga tsarkakewa zuwa bayyanar iskar gas sannan kuma sake tsaftacewa. An fara tsabtace ɗakin ta hanyar tsaftacewa tare da nitrogen a 200 cm3 na awa 1 don tabbatar da cire duk sauran masu nazarin da ke cikin ɗakin, ciki har da danshi. Sai a hankali aka saki masu nazarin ɗaiɗaikun a cikin ɗaki a daidai gwargwado na 200 cm3 ta hanyar rufe silinda na N2.
An buga sigar wannan labarin da aka sabunta kuma ana iya samun dama ta hanyar mahaɗin da ke saman labarin.
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