简介：Astrategyforthesynthesisofpolymer-protectivebimetallicsolsisproposedwhichhastheadvantageofthestrongprotectiveeffectofthepolymeragentononeofthecompositestostabilizethebimetalliccolloidalparticles.Thisstrategyiscertifiedtobeusefultothepredicationoftheformationofstablebimetalliccolloidsprotectedbypolymerandtothecontroloftheparticlesizetoacertainextent.AseriesofnewPVP-protectivebimetalliccolloidaldispersionscontainingnoblemetalelement(Pt,Rh,Pd),lighttransitionmetalelement(Co,Fe),andboronareobtainedfromthecorrespondingsaltsbythemethodsofreductionbystageandcoreduction,usingtheNaBH4asreductant.TheTEM,XRDandEPMAmeasurementsindicatetheformationofbimetalliccolloids.AninterestingkindofcoilaggregationisobservedinthesystemsofPVP-Pt-CoandPVP-Rh-Copreparedbythemethodofreductionbystage.

简介：TheSolvatedMetalAtomImpregnation(SMAI)techniquewasemployedtopreparemacroporousresinimmobilizedPd-Cubimetallicclustercatalysts.TheX-raydiffraction(XRD)andtransmissionelectronmicrograph(TEM)showedthatPd-CualloywasformedandtheparticlesizesofPd-Cuclusterswereverysmall,withaveragediameters<3nm.X-rayphotoelectronspectroscopyindicatedthatbothPdandCuwereinzero-valentstate.ThecatalyticactivitiesofthemacroporousresinimmobilizedPd-Cucatalystsinhydrogenationof4-methyl-3-penten-2-oneweremuchgreaterthanthatofthecarbonsupportedPd-Cucatalysts.

简介：由于他们的结构上的二金属的nanoparticles(NP)的化学、物理的性质的依赖，他们的结构的特征的基本理解为他们的综合体和宽应用是关键的。在这篇文章，Au-Pd二金属的NP的系统的原子水平的调查被在不同Au/Pd比率和不同尺寸与量修正Sutton陈潜力(Q-SC)使用改进粒子群优化(IPSO)进行。在IPSO，模仿的退火被介绍进古典粒子群优化(PSO)改进有效性和可靠性。另外，结构的稳定性和结构的特征上的起始的结构，粒子尺寸和作文的影响也被学习。模拟结果表明起始的结构在稳定的结构上有小效果，但是极大地影响收敛的率，并且起始的结构清楚地是的混合的集中率快核心壳和阶段比那些组织。我们发现Au-PdNP比较喜欢结构与在外部层Au富有当时在内部的Pd富有。特别，当Au/Pd比率是6:4时，nanoparticle(NP)的结构介绍标准化Pd核心Au壳结构。

简介：Bimetalliccobalt-rutheniumnanocatalystssupportedoncarbonnanotubes(CNTs)arepreparedusingmicroemultiontechniquewithwater-to-surfactantratiosof0.5—1.5.ThenanocatalystswereextensivelycharacterizedbydifferentmethodsandtheiractivityandselectivityinFischer-Tropschsynthesis(FTS)havebeenassessedinafixed-bedmicroreactor.Thephysicochemicalpropertiesandperformanceofthenanocatalystswerecomparedwiththecatalystpreparedbyimpregnationmethod.Verynarrowparticlesizedistributionhasbeenproducedbythemicroemulsiontechniqueatrelativelyhighloadingsofactivemetals(15wt%Coand1wt%Ru).AccordingtoTEMimages,smallCoparticles(2—7nm)weremostlyconfinedinsidetheCNTs.Comparingwiththecatalystpreparedbyimpregnation,theuseofmicroemulsiontechniquewithwatertosurfactantratioof0.5decreasedtheaveragecobaltoxideparticlesizeto4.8nm,thedispersionwasalmostdoubledandthereductionincreasedby28%.Activityandselectivitywerefoundtobedependentonthecatalystpreparationmethodandwater-to-surfactantratio(aswellascobaltparticlesizes).COconversionincreasedfrom59.1%to75.1%andtheFTSrateincreasedfrom0.291to0.372gHC/(gcath).C5+liquidhydrocarbonsselectivitydecreasedfrom92.4%to87.6%.

简介：Zn/ZSM-5（NZ2）andZn/Ni/ZSM-5（NZ3）asthecatalystsformethanoltoaromatics（MTA）weresynthesizedbyasimpleultrasonicimpregnation.ThetexturalandacidpropertiesofallcatalystswerecharacterizedusingXRD,HRTEM,NH3-TPD,Py-IR,XPS,XRFandTGtechniques.TheXRDandHRTEMresultsshowedthatthebasiczeolitestructureswerenotaffectedmuchwiththeincorporationofZnandNispecies.However,greatchangeshavetakenplaceinacidproperties.ThePy-IRandXPSresultsindicatedthattheZn-Lewisacidsites（ZnOH+species）,whichhavestrongerinteractionwiththezeoliteframeworkcomparedwithZnOspecies,weregeneratedattheexpenseofBacidsiteswiththeincorporationofzincspecies.Moreover,theproductanalysisresultsshowedthattheincorporationofzincspeciespromotedtheprimaryaromatizationbyenhancingthedehydroaromatizationandsuppressingthecrackingandsubsequentH-transferreaction.Furthermore,theadditionofNispecieswellinhibitedthelossofzincspeciesbyconvertingpartialZnOspeciestoZnOH+species,andthusimprovedthearomatizationactivityandcatalyststability.ThecatalyticperformanceresultsshowedthattheNZ3possesshigherconversionofmethanolinalongertimeandloweraveragerateofcokeformationcomparedwithNZ2.Inaddition,theNZ3alsoexhibitedthehighestyieldofBTXasthereactionproceeds.

简介：BimetallicFe-Mnnanocatalystssupportedoncarbonnanotubes(CNTs)werepreparedusingmicroemulsiontechniquewithwater-to-surfactantratiosof0.4-1.6.ThenanocatalystswereextensivelycharacterizedbydifferentmethodsandtheiractivityandselectivityinFischer-Tropschsynthesis(FTS)havebeenassessedinafixed-bedmicroreactor.Thephysicochemicalpropertiesandperformanceofthenanocatalystswerecomparedwiththecatalystpreparedbyimpregnationmethod.Verynarrowparticlesizedistributionhasbeenproducedbythemicroemulsiontechniqueatrelativelyhighloadingofactivemetal.TEMimagesshowedthatsmallmetalnanoparticlesintherangeof3–7nmwerenotonlyconfinedinsidetheCNTsbutalsolocatedontheoutersurfaceoftheCNTs.Usingmicroemulsiontechniquewithwatertosurfactantratioof0.4decreasedtheaverageironparticlesizesto5.1nm.Thereductionpercentageanddispersionpercentagewerealmostdoubled.Activityandselectivitywerefoundtobedependentonthecatalystpreparationmethodandaverageironparticlesize.COconversionandFTSrateincreasedfrom49.1%to71.0%and0.144to0.289gHC/(gcath),respectively.WhiletheWGSratedecreasedfrom0.097to0.056gCO2/(gcath).C5+liquidhydrocarbonsselectivitydecreasedslightlyandolefinsselectivityalmostdoubled.

简介：Theremediationofgroundwaterwhichcontainschlorinatedorganiccompounds(COCs)bynanoscalebimetalliccatalystshasreceivedincreasinginterestinrecentyears.Thisreportpresentsthedechlorinationof2,4-dichlorophenol(2,4-DCP)byPd-Febimetallicnanoparticlesinthepresenceofhumicacid(HA)toinvestigatethefeasibilityofusingPd-Fefortheinsituremediationofcontaminatedgroundwater.OurexperimentalresultsindicatedthatHAhadanadverseeffectonthedechlorinationof2,4-DCPbyPd-Fenanoparticles.Therateconstantkvaluesof2,4-DCPdechlorinationwere0.017,0.013,0.009,0.006and0.004min?1forHAconcentrationsof0,5,10,15and20mg/L,respectively.TherelationshipbetweenHAdosageandkvaluescanbedescribedasalinearmodel.

简介：镁氯化物支持了钒/钛有di-i-butylphthalate的二金属的Ziegler-Natta催化剂作为为乙烯和丙烯的copolymerization的内部施主被准备。反应温度的效果，乙烯/丙烯臼齿的比率，铝/钒(Al/V)臼齿的比率和钛/钒在催化活动的臼齿的比率被调查。分子的重量，分子的重量分发，顺序作文和产品的crystallinity被胶化浸透层析，13C-NMR和微分扫描热量测定分析分别地测量。与钒和钛催化剂相比，二金属的催化剂显示出更高催化的活动和更好的copolymerization性能。获得的乙烯/丙烯共聚物有高分子的重量(105)，宽广分子的重量分发，有随机的高丙烯内容或短堵住的顺序组织(rErP=1.919)，低融化温度和低crystallinities(Xc<20%)。

简介：ＣＡＴＡＬＹＴＩＣ　ＰＲＯＰＥＲＴＩＥＳ　ＯＦ　ＳＩＬＩＣＡ－ＳＵＰＰＯＲＴＥＤ　ＰＯＬＹ－γ－ＡＭＩＮＯＰＲＯＰＹＬＳＩＬＯＸＡＮＥ－ＲＨＯＤＩＵＭ－ＣＯＢＡＬＴ　ＢＩＭＥＴＡＬＬＩＣ　ＣＯＭＰＬＥＸ　ＦＯＲ　ＨＹＤＲＯＦＯＲＭＹＬＡＴＩＯＮＣＡＴ...

简介：Usingorganicaquaregia,arecentlydiscoveredpowerfulorganicleachingagent,aneffectiveprocessofrecoveringPtdirectlyfromPt-Aubimetallicnanoparticleswasdemonstrated.ThepuritiesofthePtrecoveredfromamixtureofAuandPtnanoparticlesandfromPt-Aucore-shellnanoparticlecatalystareashighas(99.49±0.22)％,and(95.02±0.08)％,respectively.Thenovelrecoveryprocesspromisesapplicationsincatalysisindustry.

简介：Theaerobicoxidationofglycerolprovidesaneconomicallyviableroutetoglyceraldehyde,dihydroxyacetoneandglycericacidwithversatileapplications,forwhichmonometallicPt,AuandPdandbimetallicAu–Pt,Au–PdandPt–PdcatalystsonTiO2wereexaminedunderbase-freeconditions.PtexhibitedasuperioractivityrelativetoPd,andAu–PdandPt–PdwhileAuwasessentiallyinactive.ThepresenceofAuontheAu–Pt/TiO2catalystsledtotheirhigheractivities(normalizedperPtatom)inawiderangeofAu/Ptatomicratios(i.e.1/3–7/1),andtheonewiththeAu/Ptratioof3/1exhibitedthehighestactivity.SuchpromotingeffectisascribedtotheincreasedelectrondensityonPtviatheelectrontransferfromAutoPt,ascharacterizedbythetemperature-programmeddesorptionofCOandinfra-redspectroscopyforCOadsorption.Meanwhile,thepresenceofAuonAu–Pt/TiO2,mostlikeduetotheobservedelectrontransfer,changedtheproductselectivity,andfacilitatedtheoxidationofthesecondaryhydroxylgroupsinglycerol,leadingtothefavorableformationofdihydroxyacetoneoverglyceraldehydeandglycericacidthatwerederivedfromtheoxidationoftheprimaryhydroxylgroups.ThesynergeticeffectbetweenAuandPtdemonstratesthefeasibilityintheefficientoxidationofglyceroltothetargetedproducts,forexample,byrationaltuningoftheelectronicpropertiesofmetalcatalysts.

简介：Bismuth-basedSillen-Aurivilliuscompoundsarebeingexploredasefficientphotocatalystmaterialsforthedegradationoforganicpollutantsduetotheiruniquelayeredstructurethatfavourseffectiveseparationofelectron-holepairs.Inthiswork,wesynthesizedSillen-Aurivillius-relatedBi2YO4CIwiththebandgapof2.5eVbyasimplesolid-statereactionandsensitizedwithrhodiumnickel(RhNi)nanoparticles(NPs)toformtheRhNi/Bi2YO4CIheterostructure.PhotocatalyticactivitiesofBiOCI,Bi2YO4CIandtheRhNi/Bi2YO4CIheterostructurewereexaminedforthedegradationofrhodamine-6Gundervisible-lightillumination.ResultsdemonstratedthatthephotocatalyticdyedegradationefficiencyofRhNi/Bi2YO4CIheterostructuresishigherthanthoseofBiOCIandBi2YO4CI,attributedtothesynergisticmolecular-scalealloyingeffectofbimetallicRhNiNPs.Theplausiblemechanismforthedegradationofrhodamine-6Gandtheeffectiveelectron-holepairutilizationmechanismwerediscussed.

简介：Chemicalloopingdryreforming（CLDR）isaninnovativetechnologyforCO2utilizationusingthechemicalloopingprinciple.TheCLDRprocessconsistsofthreestages,i.e.CH4reduction,CO2reforming,andairoxidation.Spinelnickelferrite（NiFe2O4）waspreparedanditsmulti-cycleperformanceasanoxygencarrierforCLDRwasexperimentallyinvestigated.X-raydiffraction（XRD）andLaserRamanspectroscopyshowedthatapurespinelcrystallinephase（NiFe2O4）wasobtainedbyaparallelflowco-precipitatingmethod.NiFe2O4wasreducedintoFe-Nialloyandwustite（FexO）duringtheCH4reductionprocess.SubsequentoxidationofthereducedoxygencarrierwasperformedwithCO2asanoxidanttoformanintermediatestate:amixtureofspinelNi1-xFe2+xO4,Fe2+yO4andmetallicNi.AndCOwasgeneratedinparallelduringthisstage.Approximate185mLofCOwasgeneratedfor1gspinelNiFe2O4inasinglecycle.TheintermediateoxygencarrierwasfullyoxidizedintheairoxidationstagetoformamixtureofNi1+xFe2-xO4andFe2O3.Althoughtheoriginalstateofoxygencarrier（NiFe2O4）wasnotfullyregeneratedandagglomerationwasobserved,agoodrecyclabilitywasshownin10successiveredoxcycles.更多还原

简介：Theequilibriumgeometries,relativestabilities,andelectronicpropertiesofMnAgm(M=Na,Li;n+m≤7)aswellaspureAgn,Nan,Lin(n≤7)clustersaresystematicallyinvestigatedbymeansofthedensityfunctionaltheory.Theoptimizedgeometriesrevealthatfor2≤n≤7,therearesignificantsimilaritiesingeometryamongpureAgn,Nan,andLinclusters,andthetransitionsfromplanartothree-dimensionalconfigurationsoccuratn=7,7,and6,respectively.Incontrast,thefirstthree-dimensional(3D)structuresareobservedatn+m=5forbothNanAgmandLinAgmclusters.Whenn+m≥5,astrikingfeatureisthatthetrigonalbipyramidbecomesthemainsubunitofLinAgm.Furthermore,dramaticodd-evenalternativebehavioursareobtainedinthefragmentationenergies,secondorderdifferenceenergies,highestoccupiedandlowestunoccupiedmolecularorbitalenergygaps,andchemicalhardnessforbothpureanddopedclusters.Theanalyticresultsexhibitthatclusterswithanevenelectronicconfiguration(2,4,6)possesstheweakestchemicalreactivityandmoreenhancedstability.