简介：Vanadiumalloyisoneofthemostimportantcandidatestructuralmaterialsforafusionreactor.Itsmainadvantagesoverothercandidatesareitslowactivityfeatureandfeasiblepropertiesathightemperature.However,vanadiumiseasilyoxidizedathightemperaturetoformanon-protectivesurfacefilmofV2O5.Oxygenconcentrationwouldthusgethighandthepropertiesgetworseinnotonlythelossoftheductilitybutalsotheenhancedhydrogenembrittlementbytheoxidation.

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简介：Theseriouscarbondepositionexistingincatalyticpartialoxidationofmethane(CPOM)tosyngasprocessisoneofthekeyproblemsthatimpedeitsindustrialization.Inthisstudy,3-dimensionalunsteadynumericalsimulationsofthesootformationandoxidationinoxidationsectioninaheatcouplingreactorwerecarriedoutbycomputationalfluiddynamics(CFD)approachincorporatingtheMoss-Brookesmodelforsootformation.Themodelhasbeenvalidatedandproventobeingoodagreementwithexperimentresults.Effectsofnozzletype,nozzleconvergenceangle,channelspacing,numberofchannels,radius/heightratio,oxygen/carbonratio,preheattemperatureandadditionalintroductionofsteamonthesootformationweresimulated.Resultsshowthatthesootformationinoxidationsectionoftheheatcouplingreactordependsonbothnozzlestructuresandoperationconditions,andthesootconcentrationcanbegreatlyreducedbyoptimizationwiththemaximummassfractionofsootinsidetheoxidationreactorfrom2.28%to0.0501%,andsothatthesootmassfractionattheexitreducesfrom0.74%to0.03%.

简介：Anewoxidationkineticsmodelisestablishedforhigh-temperatureoxidation.Weassumethattheinterfacereactionisfastenoughandtheoxidationrateiscontrolledbydiffusionprocessathightemperature.Byintroducingthegrowthstressgradientwemodifytheclassicaloxidationparaboliclaw.Themodifiedfactoroftheoxidationrateconstantisafunctionofgrowthstrain,environmentoxygenconcentration,andtemperature.Themodelingresultsshowthatthestressgradienteffectontheoxidationratecannotbeignored.Growthstrainwilldominatewhetherthestressgradienteffectpromotesorslowsdowntheoxidationprocess.Thestressgradienteffectbecomesweakerathighertemperature.Thiseffectisamplifiedathigherconcentrationsofenvironmentaloxygen.Appliedmechanicalloadsdonotaffecttheoxidationrate.Thismodelisavailableforhightemperatureoxidationofmetalsandalloys.

简介：Wateroxidation,asamandatoryreactionofsolarfuelsconversionsystems,requirestheuseoflightabsorberswithelectronicpropertiesthatarewellmatchedwiththoseofthemulti-electroncatalystinordertoachievehighefficiency.Molecularlightabsorbersofferflexibilityinfinetuningoforbitalenergetics,andmetaloxidenanoparticleshaveemergedasrobustoxygenevolvingcatalysts.Hence,thesematerialchoicesofferapromisingapproachforthedevelopmentofphotocatalyticsystemsforwateroxidation.However,efficientchargetransfercouplingofmolecularlightabsorbersandmetaloxidenanoparticlecatalystshasprovenachallenge.Recentnewapproachestowardtheefficientcouplingofthesecomponentsbasedonsyntheticdesignimprovementscombinedwithdirectspectroscopicobservationandkineticevaluationofchargetransferprocessesarediscussed.

简介：Ironoxidenanoparticles(FeO_xNPs,5–30nmsize)preparedvialaserablationinliquidweresupportedontoIndiumTinOxideconductiveglassslidesbymagnetophoreticdeposition(MD)technique.TheresultingFeOx@ITOelectrodesarecharacterizedbyalowamountofironcoverageof16–50nmol/cm~2,andshowelectrocatalyticactivitytowardswateroxidationinneutralphosphatebufferpH7with0.58VoverpotentialandquantitativeFaradaicefficiencytowardsoxygenproduction.XPSanalysisontheoxygenregionoftheFeO_xfilmsrevealsasubstantialhydrationofthesurfaceaftercatalysis,recognizedasacrucialsteptoaccessreactivity.

简介：Nanostructuredironoxyhydroxide（FeOOH）thinfilmshavebeensynthesizedusinganelectrodepositionmethodonanickelfoam（NF）substrateandeffectofairannealingtemperatureonthecatalyticperformanceisstudied.Theas-depositedandannealedthinfilmswerecharacterizedbyX-raydiffraction（XRD）,X-rayphotoelectronspectroscopy（XPS）,fieldemissionscanningelectronmicroscopy（FE-SEM）andlinearsweepvoltammetry（LSV）todeterminetheirstructural,morphological,compositionalandelectrochemicalproperties,respectively.Theas-depositednanostructuredamorphousFeOOHthinfilmisconvertedintoapolycrystallineFe2O3withhematitecrystalstructureatahightemperature.TheFeOOHthinfilmactsasanefficientelectrocatalystfortheoxygenevolutionreaction（OER）inanalkaline1MKOHelectrolyte.Thefilmannealedat200°Cshowshighcatalyticactivitywithanonsetoverpotentialof240mVwithasmallerTafelslopeof48mV/dec.Additionally,itneedsanoverpotentialof290mVtothedrivethecurrentdensityof10mA/cm2andshowsgoodstabilityinthe1MKOHelectrolytesolution.

简介：Thedevelopmentofthehydrogenelectrodeisvitalfortheapplicationofalkalinepolymerelectrolytefuelcells(APEFCs).Inthisstudy,aseriesofNi(OH)2decoratedNi/Ccatalysts(Ni(OH)2-Ni/C)werepreparedbyathree-stepelectrochemicaltreatmentofNi/C.TheexistenceofNi(OH)2wasdemonstratedbyX-rayphotoelectronspectroscopy(XPS),andthesurfacemolarratioofNi(OH)2/Niofthesampleswasestimatedviaanelectrochemicalmethod.TheHORcatalyticactivityofthecatalystswasevaluatedbyarotationdiskelectrode(RDE)method,anda'volcanoplot'wasestablishedbetweentheHORexchangecurrent(j0)andthesurfacemolarratioofNi(OH)2/Ni.Ontopofthe'volcano',thesurfacemolarratioofNi(OH)2/Niis1.1:1,thej0ofwhichwas6.8timesofthatofNi/C.ThestabilityofthesamplestowardHORwasevaluatedtobegood.OurstudyaddedasystematicexperimentalevidencetotheHORresearch,showingthattheHORcatalyticactivityofNicanbedeliberatelycontrolledviadecorationofNi(OH)2,whichmayhelpunderstandingtheHORmechanismonNi.

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简介：EfficientcatalyticoxidationofethylbenzenetoacetophenonewasrealizedusingthecatalyticsystemofcobaltzeoliticimidazolateframeworkZIF-67/N-hydroxyphthalimide(NHPI)undermildconditions.95.2%conversionofethylbenzenewith90.3%selectivitytoacetophenonecouldbeobtainedat373Kunder0.3MPaO2for9h.TheresultsshowthatthereexistssynergeticeffectbetweenZIF-67andNHPI.1-Phenylethylhydroperoxide(PEHP)wasgeneratedviaaradicalprocessinvolvingthehydrogenabstractionfromethylbenzenebyphthalimideN-oxyl,andsubsequentlyeffectivelydecomposedtoacetophenonebyZIF-67.

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简介：COandformaldehyde(HCHO)oxidationreactionswereinvestigatedovermesoporousAg/Co3O4catalystspreparedbyone-pot(OP)andimpregnation(IM)methods.Itwasfoundthattheone-potmethodwassuperiortotheimpregnationmethodforsynthesizingAg/Co3O4catalystswithhighactivityforbothreactions.ItwasalsofoundthatthecatalyticbehaviorofmesoporousCo3O4andAg/Co3O4catalystsforthebothreactionswasdifferent.AndtheadditionofsilveronmesoporousCo3O4didnotalwaysenhancethecatalyticactivityoffinalcatalystforCOoxidationatroomtemperature(20C),butcouldsignificantlyimprovethecatalyticactivityoffinalcatalystforHCHOoxidationatlowtemperature(90C).Thehighsurfacearea,uniformporestructureandtheprettygooddispersiondegreeofthesilverparticleshouldberesponsiblefortheexcellentlow-temperatureCOoxidationactivity.However,forHCHOoxidation,theadditionofsilverplayedanimportantroleintheactivityenhancement.AndthesilverparticlesizeandthereducibilityofCo3O4shouldbeindispensableforthehighactivityofHCHOoxidationatlowtemperature.

简介：Thisworkreportsafeasiblesynthesisofhighly-dispersedPtandPt-Fenanoparticlessupportedonmultiwallcarbonnanotubes(MWCNTs)withoutFeandmultiwallcarbonnanotubeswithiron(MWCNTs-Fe)whichappliedaselectrocatalystsformethanolelectrooxidation.APtcoordinationcomplexsaltwassynthesizedinanaqueoussolutionanditwasusedasprecursortopreparePt/MWCNTs,Pt/MWCNTs-Fe,andPt-Fe/MWCNTsusingFeCl24H2OasironsourcewhichwerenamedS1,S2andS3,respectively.Thecoordinationcomplexofplatinum(TOA)2PtCl6wasobtainedbythechemicalreactionbetween(NH4)2PtCl6withtetraoctylammoniumbromide(TOAB)anditwascharacterizedbyFT-IRandTGA.ThematerialswerecharacterizedbyRamanspectroscopy,SEM,EDS,XRD,TEMandTGA.TheelectrocatalyticactivityofPt-basedsupportedonMWCNTsinthemethanoloxidationwasinvestigatedbycyclicvoltammetry(CV)andchronoamperometry(CA).Pt-Fe/MWCNTselectrocatalystsshowedthehighestelectrocatalyticactivityandstabilityamongthetestedelectrocatalystsduetothattheadditionof'Fe'promotestheOHspeciesadsorptionontheelectrocatalystsurfaceatlowpotentials,thus,enhancingtheactivitytowardthemethanoloxidationreaction(MOR).

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简介：Ti6Al4Visawidelyappliedinmedicalimplantssuchasbone,joint,andteethduetoitsexcellentmechanicalproperties,corrosionresistance,plasticityandthebiocompatibilityofthesurfaceoxide.However,thenativesurfaceoxidefilmisquitethin(about5nm)andtechniquessuchasmicroarcoxidation,plasmasprayedhydroxyapatitaeandplasmaimmersionionimplantationareusedtosynthesizethickersurfacetitaniumoxide.