学科分类
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16 个结果
  • 简介:高密度碳化钨nanorod数组被劈啪作响的磁控管(MS)在碳化钨nanorod数组电极上作为template.Electrocatalytic性质ofnitromethane电镀物品减小用铝格子膜(ALM)准备了被电气化学的方法调查,并且他们的电镀物品催化活性被接近到磅陪衬电极的。

  • 标签: 炭化钨 铝元素 晶格 磁电管
  • 简介:Co(II)-salenwasencapsulatedinMIL-100(Cr)metalorganicframeworkby"shipinabottle"tosynthesizeanewelectrocatalyst,Cosalen@MIL-100(Cr).ThematerialwascharacterizedbyXRD,FT-IR,UV-VisandN2-adsorption.TheCosalen@MIL-100(Cr)modifiedglassycarbonelectrodeexhibitsawell-definedreductionpeakatthepotentialof–0.21Vtowardtheoxygenreductionreaction(ORR)bycyclicvoltammetry(CV)inpH=6.84phosphatebuffer.Almost400mVpositiveshiftofpotentialatCosalen@MIL-100(Cr)modifiedelectrodeforORRcomparedwiththatatbareglassycarbon,indicatesthatCosalen@MIL-100(Cr)possessesexcellentelectrocatalyticactivity.ThetransferrednumberofelectronsforORRwasdeterminedbychronocoulometry.TheresultsuggeststhattheintroductionofCo(II)-salencomplexintoMOFincreasestheelectrocatalyticactivityviaafour-electronreductionpathway.Furthermore,thiselectrocatalystexhibitsgoodstabilityandreproducibility.

  • 标签: 电催化还原 封装 电催化活性 玻碳电极 氧气 金属有机骨架
  • 简介:NanocrystallineNi-Mo-Fealloydepositswereobtainedbyelectrodeposition.ThestructuresofthealloydepositswereanalyzedbyX-raydiffraction(XRD)andX-rayphotoelectronspectroscopy(XPS).TheXRDresultsofnanocrystallineNi-Mo-Fealloydepositshowthatmanydiffractionlinesdisappear,andthatthereisonlyonediffractionpeakat44.0°.TheXPSresultsofnanocrystallineNi-Mo-Fealloydepositsindicatethatthenickel,molybdenumandironofthedepositsexistinmetallicstate,andthatthebindingenergyofthealloyedelementsincreasestosomeextent.ThenanocrystallineNi-Mo-FealloydepositelectrodemayofferbetterelectrocatalyticactivitythanthepolycrystallinenickeleletrodeandthenanocrystallineNi-Moalloyelectrode.TheelectrochemicalimpedancespectrafromthenanocrystallineNi-Mo-Fealloyelectrodeindicatethathydrogenevolutionin30%(m/m)KOHatloweroverpotentialisinaccordancewiththeVolmer-Tafelmechanism,butwiththeVolmer-Heyrovskymechanismathigheroverpotential.

  • 标签: 电催化 镍钼铁合金 纳米晶 电镀 电极
  • 简介:Recentadvancesontheuseofnanocarbon-basedelectrodesfortheelectrocatalyticconversionofgaseousstreamsofCO2toliquidfuelsarediscussedinthisperspectivepaper.Anovelgas-phaseelectrocatalyticcell,differentfromthetypicalelectrochemicalsystemsworkinginliquidphase,wasdeveloped.Thereareseveraladvantagestoworkingasphase,e.g.noneedtorecovertheproductsfromaliquidphaseandnoproblemsofCO2solubility,etc.Operatingundertheseconditionsandusingelectrodesbasedonmetalnanoparticlessupportedovercarbonnanotube(CNT)typematerials,longC-chainproducts(inparticularisopropanolunderoptimizedconditions,butalsohydrocarbonsuptoC8-C9)wereobtainedfromthereductionofCO2.Pt-CNTaremorestableandgiveinsomecasesahigherproductivity,butFe-CNT,particularusingN-dopedcarbonnanotubes,giveexcellentpropertiesandarepreferabletonoble-metal-basedelectrocatalystsforthelowercost.ThecontrolofthelocalizationofmetalparticlesattheinneroroutersurfaceofCNTisanimportactfactorfortheproductdistribution.ThenatureofthenanocarbonsubstratealsoplaysarelevantroleinenhancingtheproductivityandtuningtheselectivitytowardslongC-chainproducts.TheelectrodesfortheelectrocatalyticconversionofCO2arepartofaphotoelectrocatalytic(PEC)solarcellconcept,aimedtodevelopknowledgeforthenewgenerationartificialleaf-typesolarcellswhichcanusesunlightandwatertoconvertCO2tofuelsandchemicals.TheCO2reductiontoliquidfuelsbysolarenergyisagoodattempttointroducerenewablesintotheexistingenergyandchemicalinfrastructures,havingahigherenergydensityandeasiertransport/storagethanothercompetingsolutions(i.e.H2).

  • 标签: 液体燃料 催化转化 纳米碳 碳电极 二氧化碳排放量 CO2
  • 简介:Directelectrochemicalformationofhydrogenperoxide(H2O2)frompureO2andH2oncheapmetal-freeearthabundantcatalystshasemergedasthehighestatom-efficientandenvironmentallyfriendlyreactionpathwayandisthereforeofgreatinterestfromanacademicandindustrialpointofview.Veryrecently,novelmetal-freemesoporousnitrogen-dopedcarboncatalystshaveattractedlargeattentionduetotheuniquereactivityandselectivityfortheelectrochemicalhydrogenperoxideformation[1–3].Inthiswork,weprovidedeeperinsightsintotheelectrocatalyticactivity,selectivityanddurabilityofnovelmetal-freemesoporousnitrogen-dopedcarboncatalystfortheperoxideformationwithaparticularemphasisontheinfluenceofexperimentalreactionparameterssuchaspHvalueandelectrodepotentialforthreedifferentelectrolytes.Weusedtwoindependentapproachesfortheinvestigationofelectrochemicalhydrogenperoxideformation,namelyrotatingring-diskelectrode(RRDE)techniqueandphotometricUV–VIStechnique.Ourelectrochemicalandphotometricresultsclearlyrevealedaconsiderableperoxideformationactivityaswellashighcatalystdurabilityforthemetal-freenitrogen-dopedcarboncatalystmaterialinbothacidicaswellasneutralmediumatthesameelectrodepotentialunderambienttemperatureandpressure.Inaddition,theobtainedelectrochemicalreactivityandselectivityindicatethatthemechanismsfortheelectrochemicalformationanddecompositionofperoxidearestronglydependentonthepHvalueandelectrodepotential.

  • 标签: 催化剂材料 电催化活性 过氧化氢 氮掺杂 金属 介孔
  • 简介:在自我组织的TiO2nanotubes(Pt-TiO2/Ti)上支持的铂nanoparticles用cathodic减小跟随的电气化学的阳极的氧化被准备。结构和Pt-TiO2/Tielectrocatalyst的化学自然被X光检查衍射(XRD)和扫描电子显微镜学(SEM)调查。XRD和SEM结果在nanotubularTiO2上显示铂的存在。磅存款的稳定性被周期的voltammetry也在0.5mol/LH2SO4答案调查。当退火了到锐钛矿时,Pt-TiO2/Ti催化剂的electrocatalytic活动在甲醇的电镀物品氧化期间展出改进效果。Pt-TiO2/Tielectrocatalyst上的甲醇氧化的连续周期的voltammograms看唯一的electrocatalytic特征是否与体积磅催化剂上的甲醇氧化相比。当一部electroactive电影的形成发生到工作催化剂表面上时,这因为由自我组织的TiO2nanotubes上的磅粒子的磅(111)方面的吸附的公司的进一步快的氧化。

  • 标签: 二氧化钛纳米管 铂纳米颗粒 循环伏安法 甲醇氧化 电催化反应 退火
  • 简介:Thepyrolyzedcarbonsupportedferrumpolypyrrole(Fe-N/C)catalystsaresynthesizedwithorwithoutselecteddopants,p-toluenesulfonicacid(TsOH),byafacilethermalannealingapproachatdesiredtemperatureforoptimizingtheiractivityfortheoxygenreductionreaction(ORR)inO2-saturated0.1mol/LKOHsolution.Theelectrochemicaltechniquessuchascyclicvoltammetry(CV)androtatingdiskelectrode(RDE)areemployedwiththeKoutecky-LevichtheorytoquantitativelyobtaintheORRkineticconstantsandthereactionmechanisms.ItisfoundthatcatalystsdopedwithTsOHshowsignificantlyimprovedORRactivityrelativetotheTsOH-freeone.TheaverageelectrontransfernumbersforthecatalyzedORRaredeterminedtobe3.899and3.098,respectively,forthecatalystswithandwithoutTsOH-doping.Theheat-treatmentisfoundtobeanecessarystepforcatalystactivityimprovement,andthecatalystpyrolyzedat600℃givesthebestORRactivity.Anonsetpotentialandthepotentialatthecurrentdensityof-1.5mA/cm2forTsOH-dopedcatalystafterpyrolysisare30mVand170mV,whicharemorepositivethanthosewithoutpyrolized.Furthermore,thecatalystdopedwithTsOHshowshighertolerancetomethanolcomparedwithcommercialPt/Ccatalystin0.1mol/LKOH.TounderstandthisTsOHdopingandpyrolyzedeffect,X-raydiffraction(XRD),scanningelectronmicroscope(SEM)andX-rayphotoelectronspectroscopy(XPS)areusedtocharacterizethesecatalystsintermsoftheirstructureandcomposition.XPSresultsindicatethatthepyrrolic-Ngroupsarethemostactivesites,afindingthatissupportedbythecorrespondencebetweenchangesinpyridinic-NcontentandORRactivitythatoccurwithchangingtemperature.SulfurspeciesarealsostructurallyboundtocarbonintheformsofC–Sn–C,anadditionalbeneficialfactorfortheORR.

  • 标签: 氧还原反应 电催化剂 电催化活性 双掺杂 非贵金属 合成
  • 简介:Excessiveconsumptionofelectricalenergyhashamperedthewidespreadapplicationofelectrochemicaltechnologyfordegradationofvariouscontaminants.Inthispaper,aFe-basedmetallicglass(MG)wasdemonstratedasanewtypeofelectrocatalysttoeffectivelyandeconomicallydegradeanazodye.Incomparisontoothertypicalelectrodes,Fe-basedMGelectrodesexhibitaminimizeddegradationtime,andthespecificenergyis4-6ordersofmagnitudelowerthanthatofdimensionallystableanode(DSA),metal-likeboron-dopeddiamond(BDD)andotherelectrodes.Assacrificialelectrodematerials,Fe-basedMGshavelessspecificelectrodemassconsumptionthanironelectrodes.TheuseofFe-basedMGswillpromotethepracticalapplicationofelectrochemicaltechnologyandtheuseofMGsasfunctionalmaterials.

  • 标签: Metallic GLASSES Azo DYES Electrochemical degradation
  • 简介:Anovelcovalentlymodifiedglassycarbonelectrodewithβ-cyclodextrinwaspreparedviaelectropolymerizationtechniqueforthesimultaneousdeterminationofuricacid(UA),xanthine(XA),hypoxanthine(HX)anddopamine(DA).ThisnewelectrodepresentedanexcellentelectrocatalyticactivitytowardstheoxidationofUA,XA,HXandDAbycyclicvoltammetry(CV)method.Theoxidationpeaksofthefourcompoundswerewelldefinedandhadtheenhancedpeakcurrents.TheseparationpotentialsoftheoxidationpeaksforDA-UA,UA-XAandXA-HXwere150,390and360mVinCV,respectively.Bymeansofdifferentialpulsevoltammetry(DPV)method,thecalibrationcurvesintherangesof10―225,5―105,10―170and5―150μmol/LwereobtainedforUA,XA,HXandDA,respectively.Thelowestdetectionlimits(S/N=3)were5,1.25,5and1.5μmol/LforUA,XA,HXandDA,respectively.ThepracticalapplicationofthemodifiedelectrodewasdemonstratedbythedeterminationofDAinhydrochlorideinjectionandUA,XA,HXinhumanurinesamples.

  • 标签: 修饰玻碳电极 电催化氧化法 次黄嘌呤 同时测定 多巴胺 环糊精
  • 简介:RuO_2nanoparticlessupportedonmulti-walledcarbonnanotubes(CNTs)functionalizedwithoxygen(OCNTs)andnitrogen(NCNTs)wereemployedfortheoxygenevolutionreaction(OER)in0.1MKOH.Thecatalystsweresynthesizedbymetal-organicchemicalvapordepositionusingrutheniumcarbonyl(Ru_3(CO)_(12))asRuprecursor.TheobtainedRuO_2/OCNTandRuO_2/NCNTcompositeswerecharacterizedusingTEM,H_2-TPR,XRDandXPSinorderprobestructure–activitycorrelations,particularly,theeffectofthedifferentsurfacefunctionalgroupsontheelectrochemicalOERperformance.TheelectrocatalyticactivityandstabilityofthecatalystswithmeanRuO_2particlesizesof13–14nmwasevaluatedbylinearsweepvoltammetry,cyclicvoltammetry,andchronopotentiometry,showingthatthegenerationofnitrogen-containingfunctionalgroupsonCNTswasbeneficialforbothOERactivityandstability.InthepresenceofRuO_2,carboncorrosionwasfoundtobesignificantlylesssevere.

  • 标签: 多壁碳纳米管 电催化活性 析氧反应 RUO2 氮掺杂 负载
  • 简介:Anovelgas-phaseelectrocatalyticcellcontainingalow-temperatureprotonexchangemembrane(PEM)wasdevelopedtoelectrochemicallyconvertCO2intoorganiccompounds.TwodifferentCu-basedcathodecatalysts(CuandCu-C)werepreparedbyphysicalvapordepositionmethod(sputtering)andsubsequentlyemployedforthegas-phaseelectroreductionofCO2atdifferenttemperatures(70-90℃).ThepreparedelectrodesCuandCu-CwerecharacterizedbyX-raydiffraction(XRD),X-rayphotoemissionspectroscopy(XPS)andscanningelectronmicroscopy(SEM).Asrevealed,CuispartiallyoxidizedonthesurfaceofthesamplesandtheCuandCu-Ccathodiccatalystswerecomprisedofaporous,continuous,andhomogeneousfilmwithnanocrystallineCuwithagrainsizeof16and8nm,respectively.Theinfluenceoftheappliedcurrentandtemperatureontheelectro-catalyticactivityandselectivityofthesematerialswasinvestigated.Amongthetwoinvestigatedelectrodes,thepureCucatalystfilmshowedthehighestCO2specificelectrocatalyticreductionratesandhigherselectivitytomethanolformationcomparedtotheCu-Celectrode,whichwasattributedtothehigherparticlesizeoftheformerandlowerCuO/Curatio.Theobtainedresultsshowpotentialinterestforthepossibleuseofelectrical「enewableenergyforthetransformationofCO2intovaluableproductsusinglowmetalloadingCubasedelectrodes(0.5mgCucm2)preparedbysputtering.

  • 标签: C02 VALORIZATION ELECTRO-REDUCTION CU catalyst PEM
  • 简介:Carbondioxidetransformationtofuelsorchemicalsprovidesanattractiveapproachforitsutilizationasfeedstockanditsemissionreduction.Herein,wereportagas-phaseelectrocatalyticreductionofCO_2inanelectrolyticcell,constructedusingphosphoricacid-dopedpolybenzimidazole(PBI)membrane,whichallowedoperationat170°C.Pt/CandPtMo/CwithvariableratioofPt/Mowerestudiedasthecathodecatalysts.TheresultsshowedthatPtMo/CcatalystssignificantlyenhancedCOformationandinhibitedCH_4formationcomparedwithPt/Ccatalyst.CharacterizationbyX-raydiffraction,X-rayphotoelectronspectroscopyandtransmissionelectronmicroscopyrevealedthatmostMospeciesexistedasMoO_3inPtMo/CcatalystsandtheinteractionbetweenPtandMoO_xwaslikelyresponsiblefortheenhancedCOformationratealthoughthesebicomponentcatalystsingeneralhadalargerparticlesizethanPt/Ccatalyst.

  • 标签: 二氧化碳转化 电催化还原 聚苯并咪唑 磷酸掺杂 气相 双组分催化剂
  • 简介:Anovelhighgravitymulti-concentriccylinderelectrodes-rotatingbed(MCCE-RB)wasdevelopedfortheelectrocatalyticdegradationofphenolwastewaterinordertoenhancethemasstransferwiththeself-madeRuO2-IrO2-SnO2/Tianodes.Theinfluencesofelectriccurrentdensity,inletliquidcirculationflowrate,highgravityfactor,sodiumchlorideconcentration,andinitialpHvalueonphenoldegradationefficiencywereinvestigated,withtheoptimaloperatingconditionsdetermined.Theresultsshowedthatundertheoptimaloperatingconditionscoveringacurrentdensityof35mA/cm^2,aninletliquidcirculationflowrateof48L/h,ahighgravityfactorof20,asodiumchlorideconcentrationof8.5g/L,aninitialpHvalueof6.5,areactiontimeof100min,andaninitialphenolconcentrationof500mg/L,theefficiencyforremovalofphenolreached99.7%,whichwasimprovedby10.4%ascomparedtothatachievedinthenormalgravityfield.Thetendencyregardingthechangeinefficiencyforremovalofphenol,totalorganiccarbon(TOC),andchemicaloxygendemand(COD)overtimewasstudied.Theintermediatesanddegradationpathwayofphenolwerededucedbyhighperformanceliquidchromatography(HPLC).

  • 标签: high gravity RuO2-IrO2-SnO2/Ti ANODE ELECTROCATALYTIC oxidation
  • 简介:Theefficiencyofphoto-electrocatalytic(PECa)devicesfortheproductionofsolarfuelsdependsonseverallimitingfactorssuchaslightharvesting,chargerecombinationandmasstransportdiffusion.WeanalyseherehowtheyinfluencetheperformancesinPECacellshavingaphoto-anodebasedonAu-modifiedTiO2nanotube(TNT)arrays,withtheaimofdevelopingdesigncriteriatooptimizethephoto-anodeandthePECacellconfigurationforwaterphoto-electrolysis(splitting)andethanolphoto-reformingprocesses.TheTNTsampleswerepreparedbycontrolledanodicoxidationofTifoilsandthendecoratedwithgoldnanoparticlesusingdifferenttechniquestoenhancethevisiblelightresponsethroughheterojunctionandplasmoniceffects.Theactivitytestsweremadeinagas-phasereactor,aswellasinaPECacellwithoutappliedbias.Resultswereanalysedintermsofphoto-generatedcurrent,H2productionrateandphotoconversionefficiency.Particularly,asolar-to-hydrogenefficiencyof0.83%andaFaradaicefficiencyof91%wereobtainedwithoutaddingsacrificialreagents.

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  • 简介:Anewdinudeatingligandconsistingofatetraphanylporphyrinderivativecovalentlylinkedwithtris(2-benzimidazylmethyl)-amineanditshomodinudearCo-CoandheterodinnelearCo-Cucomplexesweresynthesizedandspectroscopicallycharacter-ized.Theheterobimetalliecobalt-coppercomplexbearingthreebenzimidazoleligandsforcopper,ascytochromecoxidaseac-tivesitemodel,wasappliedtothesurfaceofglassycarbonelec-trodetoshowelectrocatalytieactivityforO2reductioninaque-oussolutionatanaddityleveldosetophysiologicalpHvalue.Thekineticparametersofthiselectrocatalyticprocesswereob-tained.

  • 标签: 合成 表征 异核钴铜配合物 Co Cu 电催化活性