简介:PtRu/SnO2/Ccatalystwaspreparedinapolyolprocess,followedbyreductiontreatmentandalkalineetching.X-raydiffraction,transmissionelectronmicroscopewithenergydispersivespectrometerandXrayphotoelectronspectroscopywereusedtocharacterizethemorphology,structureandcompositionofthecatalysts.COandmethanolelectro-oxidationactivitiesofthecatalystswereevaluatedbyCOstrippingvoltammetry,cyclicvoltammetryandchronoamperometrymeasurements.ReductiontreatmentofthepreparedPtRuSnO2/CcatalystinapolyolprocessinducedtheenrichmentofSnonthesurface,inhibitingmethanoldissolutionandCOadsorptiononPt.AlkalineetchingremovedSnorSnOxandthusexposedPtRuonthesurface,resultinginenhancedactivitiesforCOandmethanolelectro-oxidationduetothesynergyeffectsofPtRuonthesurfaceandSnspeciesbeneath.
简介:WedemonstrateafacilerouteforthemassiveproductionofSnCb/carbonnanocompositeusedashigh-capacityanodematerialsofnextgenerationlithium-ionbatteries.ThenanocompositehadauniquestructureofultrafineSnO2nanocrystals(5nm,80wt%)homogeneouslydispersedinamorphouscarbonmatrix.ThisstructuredesigncanwellaccommodatethevolumechangeofLi+insertion/desertioninSnO2,andpreventtheaggregationofthenanosizedactivematerialsduringcycling,leadingtosuperiorcycleperformancewithstablereversiblecapacityof400mAh/gatahighcurrentrateof3.3A/g.
简介:Inthisstudy,wereportanefficientCdTe-SnO2quantumdot(QD)solarcellfabricatedbyheat-assisteddrop-castingofhydrothermallysynthesizedCdTeQDsonelectrospunSnO2nanofibers.Theas-preparedQDsandSnO2nanofiberswerecharacterizedbydynamiclightscattering(DLS),UV–Visspectroscopy,photoluminescence(PL)spectra,X-raydiffraction(XRD)andtransmissionelectronmicroscopy(TEM).TheSnO2nanofibersdepositedonfluorine-dopedtinoxide(SnO2)andsensitizedwiththeCdTeQDswereassembledintoasolarcellbysandwichingagainstaplatinum(Pt)counterelectrodeinpresenceofcobaltelectrolyte.TheefficiencyofcellswasinvestigatedbyanchoringQDsofvaryingsizesonSnO2.Thebestphotovoltaicperformanceofanoverallpowerconversionefficiencyof1.10%,anopen-circuitvoltage(Voc)of0.80V,andaphotocurrentdensity(JSC)of3.70mA/cm2wereobtainedforcellswithSnO2thicknessof5–6μmandcellareaof0.25cm2understandard1Sunillumination(100mW/cm2).Theefficiencywasinvestigatedforthesamesystemsunderpolysulfideelectrolyteaswellforacomparison.
简介:Zn2SnO4(ZTO)nanowireswithauniquedendriticnanostructureweresynthesizedviaasimpleone-stepthermalevaporationandcondensationprocess.ThemorphologyandmicrostructureoftheZTOnanodendritehavebeeninvestigatedbymeansoffieldemissionscanningelectronmicroscopy(SEM),x-raydiffraction(XRD)andhigh-resolutiontransmissionelectronmicroscopy(HRTEM).SEMobservationrevealedtheformationofbranchednanostructuresandshowedthateachbranchexhibitedauniqueperiodicstructureformedbyarowofoverlaidrhombohedraofZTOnanocrystalsalongtheaxisofthenanobranch.HRTEMstudiesdisplayedthatthebranchesgrewhomoepitaxiallyassingle-crystallinenanowiresfromtheZTOnanowirebackbone.ApossiblegrowthmodelofthebranchedZTOnanowiresisdiscussed.Tosuccessfullypreparebranchedstructureswouldprovideanopportunityforbothfundamentalresearchandpracticalapplications,suchasthree-dimensionalnanoelectronics,andopto-electronicnanodevices.
简介:AnewSnO_2-Fe_2O_3/SWCNTs(single-walledcarbonnanotubes)ternarynanocompositewasfirstsynthesizedbyafacilehydrothermalapproach.SnO_2andFe_2O_3nanoparticles(NPs)werehomogeneouslylocatedonthesurfaceofSWCNTs,asconfirmedbyX-raydiffraction(XRD),transmissionelectronmicroscope(TEM)andenergydispersiveX-rayspectroscopy(EDX).Duetothesynergisticeffectofdifferentcomponents,theassynthesizedSnO_2-Fe_2O_3/SWCNTscompositeasananodematerialforlithium-ionbatteriesexhibitedexcellentelectrochemicalperformancewithahighcapacityof692mAh·g~(-1)whichcouldbemaintainedafter50cyclesat200mA·g~(-1).Evenatahighrateof2000mA·g~(-1),thecapacitywasstillremainedat656mAh·g~(-1).
简介:通过Cu纳米颗粒掺杂制备了Li[(Ni0.6Co0.2Mn0.2)1-xCux]O2三元正极材料,并通过调节Cu的掺杂量,讨论了Cu的掺入对Li[(Ni0.6Co0.2Mn0.2)1-xCux]O2三元正极材料晶体结构、表面形貌、电化学性能和循环性能等一系列性能的影响,铜掺杂量为x=0.01时,在0.2C倍率下的首次放电比容量达到了219.1mAh/g,经过50次充放电循环之后,剩余比容量为115.4mAh/g。最终结果为Li[(Ni0.6Co0.2Mn0.2)1-xCux]O2中Cu的掺入量为x=0.01时,所得正极材料的电化学性能和循环性能最为优异。
简介:ThesplittingofpotentialenergylevelsforgroundstateX2ΠgofOx2(x=+1,1)underspin–orbitcoupling(SOC)hasbeencalculatedbyusingthespin–orbit(SO)multi-configurationquasi-degenerateperturbationtheory(SO-MCQDPT).TheirMurrell–Sorbie(M–S)potentialfunctionsaregained,andthenthespectroscopicconstantsforelectronicstates2Π1/2and2Π3/2arederivedfromtheM–Sfunction.TheverticalexcitationenergiesforOx2(x=+1,1)areν[O+12(2Π3/2→X2Π1/2)]=195.652cm1,andν[O12(2Π1/2→X2Π3/2)]=182.568cm1,respectively.Allthespectroscopicdataforelectronicstates2Π1/2and2Π3/2aregivenforthefirsttime.