ଲେଖକ: ଆଇଫ୍ଲୋପାୱାର - Umhlinzeki Wesiteshi Samandla Esiphathekayo
Daim ntawv nyias zoo li oxidized graphite txheej tau ua tiav tiav los ntawm kev hloov kho Hummers, thiab cov ntawv npaj zoo li oxidation graphite txheej raug txo qis raws li graphene nanomaterial nrog hydrazine. Synthesis khoom los ntawm Fourier transform infrared spectroscopy (FT-IR), Raman Spectroscopy (RS), X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Transmitting Electroractor (TEM), thiab Agency (AFM), thiab lwm yam. Cov qauv thiab kev ua tau zoo yog tus yam ntxwv.
Cov txiaj ntsig tau pom tias lub thickness ntawm graphene yog 0.36 nm, tus naj npawb ntawm cov txheej yog 3. Tsis tas li ntawd, cov tshuaj tiv thaiv ntawm txoj kev hloov Hummers tau npaj los ntawm cov tshuaj tiv thaiv ntawm cov ntawv nyias zoo li oxidation graphite, thiab cov txheej txheem tshuaj tiv thaiv tshwm sim thaum lub sij hawm oxidation ntawm graphite oxidation raug tshuaj xyuas.
Nyob rau hauv 2004, GEIM li al, tau npaj ib tug tshiab ob-dimensional atomic siv lead ua-graphene muaj li ntawm SP2 hybridized carbon atomic txheej siv txhua yam stripping txoj kev. Lub hauv paus txheej txheem ntawm graphene yog benzene rau yuan nplhaib, uas tsuas yog 0.34 nm.
Yog li ntawd, graphene muaj ntau yam zoo heev ntawm lub cev chemistry, xws li 100 npaug ntawm lub zog ntawm cov hlau, mus txog 130gPa, cov cab kuj mus txog 15000 cm2 / (v·s), thermal conductivity yog 5000W / (m·K). Tsis tas li ntawd, graphene kuj muaj cov khoom tshwj xeeb xws li chav tsev kub quantum Hall nyhuv thiab chav kub ferromagnetic zog. Tam sim no, txoj kev npaj ntawm graphene feem ntau yog micro-mechanical stripping txoj kev, tshuaj vapor deposition, tshuaj redox txo txoj kev, siv lead ua epitaxial txoj kev loj hlob thiab hnyav cua sov txoj kev.
Ntawm lawv, micromechanical stripping txoj kev tuaj yeem npaj graphene ntawm micron loj, tab sis kev tswj tau qis, nws nyuaj rau ua tiav cov khoom loj. Txoj kev loj hlob siv lead ua epitaxial yog qhov yooj yim rau kev tsim kho dua tshiab vim yog lub ntsej muag ntawm SiC siv lead ua, kom thaj tsam loj, lub thickness yog sib npaug rau ib qho graphene. Cov txheej txheem tshuaj vapor deposition (CVD) yog substrate nrog ib tug hlau ib leeg siv lead ua los yog ib tug hlau zaj duab xis, uas yuav loj hlob ib tug nyias txheej graphene daim ntawv txheej, tab sis lub graphene purity tsis siab, thiab loj-scale ntau lawm ua tsis tau.
Cov txheej txheem kub hnyav yog vim muaj qhov hnyav xws li qhov kub thiab txias, thiab cov khoom siv hluav taws xob tsawg, thiab tsis muaj peev xwm ua tau ntau lawm. Cov tshuaj redox txo txoj kev yog los npaj graphene los ntawm ultrasonic stripping thiab txo cov txheej txheem los ntawm Hummers txoj kev. Vim lub voj voog luv luv ntawm cov txheej txheem, qhov zoo ntawm cov khoom hluavtaws siab tau cuam tshuam thiab kev kawm.
Thaum lub sij hawm Hummers txoj kev, cov graphite yog npaj, nrog rau qhov kub thiab txias (0 ° C), nruab nrab kub (38 ° C) thiab siab kub (98 ° C), thiab oxidizing tus neeg sawv cev yog concentrated H2SO4 thiab KMNO4. Los ntawm kev kawm txog cov txheej txheem graphite oxidation, Hummers txoj kev yog hloov, uas yog, lub sij hawm nyob rau hauv lub nruab nrab kub cov tshuaj tiv thaiv theem yog ncua, thiab lub siab kub tshuaj tiv thaiv theem yog muab tso tseg. Tshem tawm cov txheej txheem tshuaj tiv thaiv ntawm qhov kub thiab txias theem, tsis tsuas yog zam lub eruptism phom sij los ntawm sulfuric acid thaum lub sij hawm kub siab, tab sis kuj tsis txhob thermal decomposition cov tshuaj tiv thaiv nyob rau hauv lub kub kub theem, txo cov degree ntawm oxidation ntawm graphite.
Hauv kev tshawb xav thiab kev sim, cov txheej txheej oxide txheej tuaj yeem npaj tau nyob rau hauv qhov kub thiab txias thiab muaj kev nyab xeeb thiab ruaj khov. Kev npaj graphite raug txo los ntawm hydrate hydrate los npaj graphene nanomaterials, thiab cov ntawv npaj nyias zoo li oxide graphite thiab graphene khoom tau tsim. 1, kev sim 1.
1, raw khoom nplai graphite (granularity: 325 mesh, thawj-nplua nuj nanotechnology Co., Ltd.); concentrated sulfuric acid (95% ~ 98%); poov tshuaj permanganate, sodium nitrate, hydrogenated (30%), hydrochloric acid, chlorination barium, hydrate (80%), thiab lwm yam.
raug tshuaj xyuas. Cov tshuaj saum toj no tsis tau hais tshwj xeeb, thiab lawv tau yuav los ntawm Shanghai Chemical Reagent Company ntawm Tuam Tshoj Pharmaceutical Group. Tag nrho cov saum toj no reagents tsis tau ncaj qha.
1.2, qauv kev npaj 1) nyias daim ntawv zoo li oxide ink (GO) txheej npaj ntawm 230 mL (98%) concentrated sulfuric acid nyob rau hauv 1000 ml ntawm peb lub khob, nyob rau hauv tas li kub sib nqus quab yuam thiab dej khov da dej, 5.0 gnano3 thiab 10.
0 g Sib tov ntawm graphite, stirring nruab nrab ntawm nruab nrab ceev rau 30 min, kom nws yog tov. 30GKMNO4 maj mam ntxiv rau qhov sib tov, thiab nplawm ntawm 0 ° C rau 2 h. Peb lub khob tau hloov mus rau hauv qhov dej kub tsis tu ncua uas tau hloov kho mus rau qhov kub ntawm ib ncig ntawm 38 ° C, txuas ntxiv rau 30 h, thiab qhov nruab nrab kub cov tshuaj tiv thaiv tau ua tiav.
Tom qab qhov ntsuas kub ntawm qhov nruab nrab qhov kub thiab txias, qhov sib tov tau hloov mus rau hauv 2000 ml beaker, diluted nrog dej deionized rau 1000 mL, thiab 200 mL (5%) H2O2 ntxiv, thiab cov tshuaj tiv thaiv ua kua hloov mus rau hauv cov xim kub. Lub centrifugation tau ua tiav nrog lub siab ceev centrifuge, thiab kev sib hloov ceev yog 4000 r / min, ntxuav nrog pre-pre-preformed 5% HCl thiab deionized dej kom txog rau thaum cov sulfuric acid sulfuric acid nyob rau hauv lub filtrate tau kuaj pom, thiab lub ncua kev kawm ntawv raug tshem tawm nyob rau hauv lub vacuum qhuav 6 daim ntawv evaporation. oxidized graphite. 2) Qhov txo qis ntawm graphene tau tawg nyob rau hauv 100 ml ntawm cov txiaj ntsig graphite ink hauv 100 ml ntawm cov tshuaj aqueous kom tau txais cov xim daj-daj raug tshem tawm, thiab cov xwm txheej ultrasound tau tawg nyob rau hauv peb lub qhov ncauj hwj, rhuab mus rau 90 ° C, drip 2 ml ntawm hydrated hydrate filtered, ntawm no 2 thiab ntau yam tshuaj tiv thaiv. lub sij hawm nrog methanol thiab dej, thiab graphene tau qhuav dhau 60 ° C.
1.3, xeem thiab characterization XRD diffraction tsom xam siv Japanese Rigaku D / MAX-RB diffractometer (Cu phiaj, Kα hluav taws xob, λ = 0.154056 nm), scanning range 5 ° ~ 80 °; infrared spectroscopy (FT-IR) tsom xam ThermonicoLET&39;s NEXUS Fourier transform infrared spectrum, KBR ntsiav tshuaj, wavelength ntau yam 400 ~ 4000cm-1; Raman spectroscopy (Raman) soj ntsuam INVIA-hom microclassless laser Raman spectrometer ntawm British Renishaw, Cov ntaub ntawv ntau yog los ntawm 100 txog 3200 cm-1, laser wavelength yog 785 nm, spatial daws teeb meem yog 1 μm lateral direction, longitudinal rau 1 μm; scanning electron microscope (SEM) txais S-4800 FESEM scanning electron microscope; transmissive electron microscope (TEM) txais Nyiv JEO lub tuam txhab JEM-2100F-hom teb xa cov kev daws teeb meem kis tau tus mob electron microscope; atomic force scanning probe microscope (AFM) txais US Veeco&39;s Nanoscope4-type atomic force microscope.
Xaus a. Los ntawm kev txheeb xyuas cov txheej txheem oxidation ntawm graphite oxidation txheej txheem, hloov Hummers txoj kev uas lub siab kub cov tshuaj tiv thaiv theem raug tso tseg, thiab cov graphene tau los ntawm ultrasound tev thiab hydrated hydrate txo kev kho mob. B.
TEM thiab AFM xeem cov qhabnias qhia tau hais tias lub thickness ntawm graphene yog 0.36 nm, tus naj npawb ntawm txheej yog 3. c.
Txoj kev muaj kev nyab xeeb thiab yooj yim, cov zis yog loj, yooj yim rau kev tswj, muab ceev thiab yooj yim, loj-scale npaj ntawm nyias daim ntawv-shaped graphene, muab lub hauv paus rau kev lag luam daim ntawv thov ntawm graphene. .