简介：Synthesis,structureandmagneticpropertiesofRudopedperovskitestructuredmanganiteLa0.5Sr0.5MnO3wereinvestigatedexperimentally.Ahydrothermalmethodwasusedforthepreparationofthesamples.Ahigh-temperatureannealingprocesswasalsoemployedtomakeacomparison.AslightlyenhancementoftheunitcellvolumewasobservedwiththeincreaseofRuconcentration.Scanningelectronmicroscopyshowsthatthematerialsaremadeupofcube-shapedparticleswithdimensionofseveralmicrometers.Importantly,itisfoundthatboththeCurietemperatureTCandsaturationmomentcanbereducedbyRudoping.ThevalueofcoercivefieldisnotaffectedbytheintroductionofRu.

简介：Severecapacityfadingandpoorhighrateperformanceoflithiumsulfur(Li-S)batterycausedby"shuttleeffect"andlowconductivityofsulfurhampersitsfurtherdevelopmentsandapplications.Li4Ti50i2(LTO)possesseshigh1whiumionconductivity,anditisalsocanbeusedasanactiveadsorbentforpolysulfide.Herein,fineLTOparticlecoatedcarbonnanofibers(CNF)werepreparedandaconductivenetworkbothforelectronandlithiumionwasbuilt,whichcangreatlypromotetheelectrochemicalconversionofpolysulfideandimprovetherateperformanceofLi-Sbatteries.Meanwhile,aquantityofadsorptionsitesisconstructedbydefectsofthesurfaceofLTO-CNFmembranetoeffectivelyimmobilizepolysulfide.ThemultifunctionalLTO-CNFinterlayercouldimpedetheshuttleeffectandenhaneecomprehensiveelectrochemicalperformanceofLi-Sbatteries,especiallyhighrateperformanee.WithsuchLTO-CNFinterlayer,theLi-Sbatterypresentsaspecificcapacityof641.9mAh/gat5Crate.After400cyclesat1C,acapacityof618.0mAh/gisretained.ThisworkprovidesafeasiblestrategytoachievehighperformanceofLi-Sbatteryforpracticalutilization.

简介：Uptothisdate,researchersarestillfacingdifficultiestoexpandthetechnologyofdirectmethanolfuelcells(DMFCs)becauseofthehighoverpotentialrequiredtooxidizethemethanolanditsrelativelypoorperformanceduetoCOpoisoningoftheleading-highcostanodecatalyst.Inlinewiththis,wehavesuccessfullymodifiedthemorphologicalstructureandcompositionoflowcostcobaltbased-metaloxides,MCo2O4(M=ZnandNi),withthesimpleandnobleuseofpolyvinylpyrrolidone(PVP)asgrowthmodifierandsurfacestabilizerduringthesynthesisofnanoparticlesinourpreviousreports,whichshownhighelectrocatalyticactivityandstrongstability.DuetothegoodperformanceofourPVPmodifiedMCo2O4towardspseudocapacitorandoxygenevolutionreactionapplications,wedecidedtoextendourresearchstudytomethanoloxidationreaction.Remarkably,PVPmodifiedNiCo2O4electrodedirectlygrownonnickelfoamsubstrateviaasimplehydrothermalprocessexhibitedbetterperformancecomparedwithPVPmodifiedZnCo2O4andNiCo2O4withoutPVP.Ithadobtainedaremarkablylowonsetpotentialof0.285Vandhighcurrentdensityof280mAcm-2,andshowngreatstabilityandhighpoisontoleranceduringacontinuousCVcyclingandChronoamperometrytest,whichattainedhighefficiencyof86.86%and98.52%,respectively.ThesepositiveresultsofPVPmodifiedNiCo2O4electrodetowardsMORmightbeattributedtoitshierarchical3Dnanostructureswithhighlymesoporoussurfaceandlargesurfaceareawhichmayhaveprovidednumerouselectroactivesites,andtheexceptionalcorrosionstabilityofNiCo2O4electrodeinalkalinesolution.

简介：A60%Fe/Al2O3catalystwaspreparedbytheco-precipitationmethod.ItwasreducedbyH2toproducemetallicFe,whichwasthensulfidedbyCS2toFe0.96SandFe3S4orphosphidedbytriphenylphosphine(PPh3)inliquidphasestoFe2PandFeP.Itwasfoundthattheironsulfides(Fe0.96SandFe3S4)exhibitedthelowactivityforthehydrodesulfurization(HDS)reactions.TheHDSactivitywasalsolowontheFe(metal)/Al2O3andFe2P/Al2O3catalystssincetheywereconvertedintoFe0.96SandFe3S4duringtheHDSreactions.Incontrast,theFeP/Al2O3wasfoundtobestableandactivefortheHDSreactions.Inparticular,FeP/Al2O3possessedsignificantlysmallerFePparticlesthanFeP/C,leadingtothesignificanthigherHDSactivityofFeP/Al2O3thanFeP/C.

简介：Inthispaper,AgBF4/[emim][BF4]supportedionicliquidmembranes(SILMs)werepreparedsuccessfullyforCO/N2separationusingnitrogenpressureimmobilizationprocedures.TheincorporationofAgBF4coulddecreasemembraneweightloss,improvethepressure-resistantability,andkeepthecriticalpressure(0.45MPa)oftheSILMs.ThehighviscosityandundissolvedAgBF4solidsinmembraneliquidwoulddisturbgasmoleculartransportthroughmembraneandgiverisetothegastransportresistance.Therefore,thegaspermeabilitydecreasedremarkablywithincreasingAgBF4carriercontentinthemembrane.WhenthemolarratioofAgBF4to[emim][BF4]increasedfrom0:1to0.3:1,theCO/N2selectivityoftheSILMsshowedagreatincreasefrom~1to~9at20°Cand0.4MPa,suggestingthatAgBF4wasaneffectivecarrierforCOfacilitatedtransport.ThepermeabilitiesofN2andCOincreasedathighertransmembranepressure,indicatingthatmoleculartransportwoulddominatethetransportprocessathighpressure.Thetemperature-dependentgaspermeabilityfollowedtheArrheniusequation.Moreover,thedifferencesbetweentheactivationenergiesofCOandN2becamelargerafterintroducingAgBF4,resultinginmoreobviousdecreaseintheCO/N2selectivityathigheroperatingtemperature.

简介：Nanosheet(S)andnanoplate(P)γ-Al2O3weresynthesizedbysimplehydrothermalmethodsandemployedassupportsforNicatalystsinCO2methanation.BothofthenanostructuredNi/Al2O3catalystsdisplayedgoodactivity.Incomparison,theNi/Al2O3-ScatalystshowedhigherCO2conversionthantheNi/Al2O3-Pcounterpartatthereactiontemperaturerangingfrom250to400°C.ThephysicalandchemicalpropertiesofthecatalystsweresystematicallycharacterizedbyN2sorption,X-raydiffraction(XRD),highresolution-transmissionelectronmicroscopy(HR-TEM),hydrogentemperature-programmedreduction(H2-TPR)andCO2temperature-programmeddesorption(CO2-TPD)techniques.Higherspecificsurfaceareaandstrongermetal-supportinteractionswereconfirmedontheNi/Al2O3-Scatalyst,whichmayleadtosmallerparticlesizeofNinanoparticles.Moreover,theNi/Al2O3-Scatalystpossessedmoreabundantweakandmediumbasicsites,whichwouldbenefittheactivationofCO2.ThesmallerNisizeandmoresuitablebasicsitesmayrationalizethesuperioractivityoftheNi/Al2O3-Scatalyst.Besides,theNi/Al2O3-Scatalystexhibitedexcellentstabilityat325°Cfor40h.

简介：AfacilehydrothermalmethodwasdevelopedforthepreparationofFe2O3@CnanocompositesusingFeCl3·6H2Oasironsourceandglucoseascarbonsourceunderalkalinecondition.Themorphologyandstructureoftheas-preparedproductwereidentifiedbytransmissionelectronmicroscopy(TEM),highresolutiontransmissionelectronmicroscopy(HRTEM),field-emissionscanningelectronmicroscopy(FESEM),X-raydiffraction(XRD),Ramanspectroscopy,FourierTransforminfraredspectroscopy(FTIR),andthermogravimetricanalysis(TGA).Theas-prepareα-Fe2O3@Cnanocompositeswereemployedforsupercapacitorelectrodematerial.Thesynergisticcombinationofcarbonelectricaldouble-layercapacitanceandα-Fe2O3pseudo-capacitanceestablishedsuchnanocompositesasversatileplatformforhighperformancesupercapacitors.Thesynthesismethoddevelopedhereisexpectedtoobtainothermetaloxide/carboncomposite.

简介：Ultrafastfiberlasersareingreatdemandforvariousapplications,suchasopticalcommunication,spectroscopy,biomedicaldiagnosis,andindustrialfabrication.Here,wereportthehighlystablefemtosecondpulsegenerationfromaMXenemode-lockedfiberlaser.Wehavepreparedthehigh-qualityTi3C2Txnanosheetsviatheetchingmethod,andcharacterizedtheirultrafastdynamicsandbroadbandnonlinearopticalresponses.Theobviousintensity-andwavelength-dependentnonlinearresponseshavebeenobservedandinvestigated.Inaddition,ahighlystablefemtosecondfiberlaserwithsignal-to-noiseratioupto70.7dBandcentralwavelengthof1567.3nmhasbeendelivered.Thestudymayprovidesomevaluabledesignguidelinesforthedevelopmentofultrafast,broadbandnonlinearopticalmodulators,andopennewavenuestowardadvancedphotonicdevicesbasedonMXenes.

简介：用微波高温固相法合成了Er^3+单掺Lu2O3,Li^+与Er^3+共掺Lu2O3及Li^+,Zn^2+,Mg^2+掺杂Lu2O3∶Er^3+的荧光粉。实验表明金属离子Li^+、Zn^2+、Mg^2+、Er^3+掺杂Lu2O3,不影响Lu2O3的立方晶相。扫描电子显微镜测量表明,Li^+掺杂可以有效改善粉体的分散性和形貌,Li^+,Zn^2+,Mg^2+共掺杂获得的粉体颗粒分布更加均匀,粒径范围为80~100nm。379nm激发下,Li^+与Er^3+共掺样品发光较单掺Er^3+样品在565nm处的发光增强了4.5倍,而Li^+、Zn^2+、Mg^2+与Er^3+共掺样品较其发光增强5.3倍。980nm激发下,Li^+与Er^3+共掺样品,Li^+、Zn^2+、Mg^2+与Er^3+共掺样品的发光分别比单掺Er^3+样品在565nm处发光增强23倍与39倍,在662nm处发光强度分别增强20倍与43倍。379nm激发下,较单掺Er3+的样品,掺杂Li^+的样品和Li^+,Zn^2+,Mg^2+和Er^3+共掺的样品荧光寿命均有所增加,而Zn^2+、Er^3+共掺及Mg^2+、Er^3+共掺样品的荧光寿命则有所缩短。

简介：WehavesynthesizedandinvestigatedphysicalpropertiesoftwonewquaternarycompoundsGd2CoAl4T2(T=Si,Ge)singlecrystals,whichareisostructuraltoTb2NiAl4Ge2andEr2CoAl4Ge2.Themostimportantstructuralfeatureofthesematerialsistheanti-CaF2-typeCoAl4T2slabs.Thesematerialsshowmetallicbehaviorbelow300Kandthereisalong-rangeantiferromagnetic(AFM)transitionappearingat20and27KforGdCoAl4Ge2andGd2CoAl4Si2,respectively.ResistivityandheatcapacitymeasurementsalsoconfirmthesebulkAFMtransitions.Furtheranalysisindicatesthatthislong-rangeantiferromagnetismshouldresultfromthemagneticinteractionbetweenlocalmomentsofGd^3+ions.

简介：Thesuppressionoftherecombinationofelectronsandholes(e–h)andtheenhancementofthelightabsorptionofsemiconductorsaretwokeypointstowardefficientphotocatalyticdegradation.Here,wereportafew-layerg-C3N4/α-MoO3nanoneedles(flg-C3N4/α-MoO3NNs)all-solid-stateZ-schememechanismphotocatalystsynthesizedviaatypicalhydrothermalmethodinacontrolledmanner.Therecombinationofthephoto-inducede–hpairscouldbeeffectivelyrestrainedbytheZ-schemepassagewaybetweentheflg-C3N4andα-MoO3NNsinthecomposite,whichcouldalsopromiseahighredoxabilitytodegradepollutants.Anditbecamepossibleforthepreparedphotocatalysttoabsorblightinawiderangeofwavelengths.Thedetailedmechanismwasstudiedbyelectronspin-resonancespectroscopy(ESR).Thelow-dimensionalnanostructureofthetwoconstituents(α-MoO3NNswithone-dimensionalstructureandflg-C3N4withtwo-dimensionalstructure)endowedthecompositewithvarietiesofexcellentphysicochemicalproperties,whichfacilitatedthetransferanddiffusionofthephotoelectronsandincreasedthespecificsurfaceareaandtheactivesites.The10wt%flg-C3N4/α-MoO3NNsshowedthebestphotocatalyticperformancetowardRhBdegradation,therateofwhichwas71.86%,~2.6timeshigherthanthatofα-MoO3NNs.