学科分类
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16 个结果
  • 简介:Theadsorptionandelectronicpropertiesofisolatedcobaltphthalocyanine(CoPc)moleculeonanultrathinlayerofNaClhavebeeninvestigated.High-resolutionSTMimagesgiveadetailedpictureofthelowestunoccupiedmolecularorbital(LUMO)ofanisolatedCoPc.ItisshownthattheNaClultrathinlayerefficientlydecouplestheinteractionofthemoleculesfromtheunderneathmetalsubstrate,whichmakesitanidealsubstrateforstudyingthepropertiesofsinglemolecules.Moreover,strongdependenceoftheappearanceofthemoleculesonthesamplebiasintheregionofrelativelyhighbias(>3.1V)isascribedtotheimagepotentialstates(IPSs)ofNaCl/Cu(100),whichmayprovideuswithapossiblemethodtofabricatequantumstoragedevices.

  • 标签: STM图像 NACL 酞菁钴 状态 分子轨道 介导
  • 简介:Asamemberof1Dnanostructuredmaterials,theferromagneticandnonmagneticmultilayernanowiresexhibittremendouspotentialapplicationsinmanyfieldsduetotheiruniquemagneticandelectricalproperties.Thebasicpropertyofmultilayernanowirearrays,suchascoercivity,iscrucialimportantforthefutureapplication.Inordertoobtainthecoercivityinformation,besidesdirectlymeasuringitthroughexperiment,theoreticalcalculationalsoprovidesausefulandfastwaytoevaluatethemultilayer’scoervicity.Fig.1(a)and(b)demonstrateasinglemultilayernanowireandnanowirearraysembodiedinamatrix,respectively.Inthiswork,byimprovingPant’smodel,wedevelopedthenewmodelandsuccessfullypredictedtherelationshipbetweenthecoercivitychangingofCu/Nimultilayernanowirearraysandstructualparameters.Fig.

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  • 简介:第三的Ni-5%Cu-5%Sn和Ni-10%Cu-10%Sn合金的液体状态undercoolability和水晶生长动力学被玻璃fluxing方法调查。在这二合金,304K的试验性的最大的undercoolings(0.18TL)和286K(0.17TL)被完成,树枝状的生长速度分别地达到39.8和25.1m/s。从进equiaxed结构的粗糙的树突的形态学的转变发生并且谷物尺寸(Ni)当undercooling增加时,显著地分阶段执行减少。格子常数和microhardness与undercooling的改进显然增加。Cu和Sn溶质内容的丰富减少树枝状的生长速度,当时提高格子常数和microhardness(Ni)阶段。

  • 标签: 三元铜镍锡合金液态 undercoolability 晶体生长动力学
  • 简介:AnefficientprocessfortheconversionofdimethyloxalateintoethyleneglycolwithhighselectivityandhighyieldoverCu2Owasinvestigated.InsituformedCuasatruecatalyticallyactivespeciesshowedagoodcatalyticperformanceforDMOconversiontoproduceEGin95%yield.

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  • 简介:Inrecentyears,themagneticmultilayerednanomaterialshavebeenextensivelystudiedforelectronics[1],ultrahightensilestrength[2],highstoragemedia[3],andmicrowavedevices[4]sincethegiantmagnetoresistance(GMR)effectwasfoundin1988.Asamemberof1Dnanostructuredmaterials,theferromagneticandnonmagneticmultilayernanowiresalsoexhibittremendouspotentialapplicationsinmanyfieldsduetotheiruniquemagneticandelectricalproperties.Inthiswork,theCu/NimultilayernanowirearraysarepreparediniontracktemplatewithelectrodepositionmethodandanewfacilemethodisfirstintroducedtoeasilyconfirmthedifferentlayerthicknessandcomponentbyremovingthenonmagneticlayerofCu.

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  • 简介:Inthiswork,anewphotocatalytsIn(0.1),Cu(x)-ZnS(x=0.01,0.03,0.05)issuccessfullysynthesizedusingsimplehydrothermalmethod.ThephysicalandchemicalpropertiesoftheInandCuco-dopedZnSphotocatalystwerecharacterizedbyX-raydiffraction(XRD),fieldemissionscanningelectronmicroscopy(FESEM),diffusereflectanceUV-visiblespectroscopy(DRUV-visible)andphotoluminescencespectroscopy(PL).Thephotocatalyticactivityoftheas-preparedInandCuco-dopedZnSforhydrogenproductionfromwaterwithNa2SO3andNa2Sassacrificialagentundervisiblelightirradiation(λ≥425nm)wasinvestigated.Thepresenceofco-dopantsfacilitatedtheseparationofelectron-holeaswellasincreasesthevisiblelightabsorption.Theabsorptionedgeoftheco-dopedZnSphotocatalystshiftedtolongerwavelengthastheamountofCuincreases.ThisindicatesthattheabsorptionpropertiesdependedontheamountofCudoped.ThephotocatalyticactivityofsingledopedIn(0.1)-ZnSwassignificantlyenhancedbyco-dopingwithCuundervisiblelightirradiation.ThehighestphotocatalyticactivitywasobservedonIn(0.1),Cu(0.03)-ZnSwiththehydrogenproductionrateof131.32μmol/hundervisiblelightirradiation.Thisisalmost8timeshigherthansingledopedIn(0.1)-ZnS.

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  • 简介:Theglass-formingability(GFA)andmagneticpropertiesoftheGd_(50)Coso-basedamorphousaiioywithAladditionsubstitutionforCoareinvestigated.ItisfoundthattheGFAandmagneto-caloriceffectoftheGd_(50)Co_(45)Al_5amorphousaiioyarebetterthanGd_(50)Co_(50)amorphousalloy.Themaximummagneticentropychange(-△S_m~(peak))andthemagneticrefrigerantcapacityoftheamorphousalloyunderafieldof5Tareabout6.64J·kg~(-1)K~(-1)and764J·kg~(-1),respectively.Thefielddependenceofmagneticentropychangemeetstheonepredictedbythemeanfieldtheory,whichisinvestigatedforabetterunderstandingofthemagneto-caloricbehaviorsoftheGd_(50)Co_(45)Al_5amorphousalloy.

  • 标签: 玻璃形成能力 共晶合金 钴基非晶合金 磁性能 磁热效应 制冷能力
  • 简介:AnewlayeredCu-basedoxychalcogenideBa3Fe2O5Cu2S2hasbeensynthesizedanditsmagneticandelectronicpropertieswererevealed.Ba3Fe2O5Cu2S2isbuiltupbyalternativelystacking[Cu2S2]2-layersandironperovskiteoxide[(FeO2)(BaO)(FeO2)]2-layersalongthecaxisthatareseparatedbybariumionswithFe3+fivefoldcoordinatedbyasquare-pyramidalarrangementofoxygen.Fromthebondvalencearguments,weinferredthatinlayeredCuCh-based(Ch=S,Se,Te)compoundsthe+3cationinperovskiteoxidesheetprefersasquarepyramidalsite,whilethelowervalencecationprefersthesquareplanarsites.Thestudiesonsusceptibility,transport,andopticalreflectivityindicatethatBa3Fe2O5Cu2S2isanantiferromagneticsemiconductorwithaNe′eltemperatureof121Kandanopticalbandgapof1.03eV.Themeasurementofheatcapacityfrom10Ktoroomtemperatureshowsnoanomalyat121K.TheDebyetemperatureisdeterminedtobe113K.TheoreticalcalculationsindicatethattheconductionbandminimumispredominantlycontributedbyO2pand3dstatesofFeionsthatantiferromagneticallyarrangedinFeO2layers.TheFe3dstatesarelocatedatlowerenergyandresultinanarrowbandgapincomparisonwiththatoftheisostructuralSr3Sc2O5Cu2S2.

  • 标签: 钙钛矿型氧化物 铁磁半导体 光学带隙 德拜温度 电子性质 阳离子
  • 简介:High-performancethin-filmtransistors(TFTs)withalowthermalbudgetarehighlydesiredforflexibleelectronicapplications.Inthiswork,theTFTswithatomiclayerdepositedZnO-channel/Al_2O_3-dielectricarefabricatedunderthemaximumprocesstemperatureof200℃.First,weinvestigatetheeffectofpost-annealingenvironmentsuchasN_2,H_2-N_2(4%)andO_2onthedeviceperformance,revealingthatO_2annealingcangreatlyenhancethedeviceperformance.Further,wecomparetheinfluencesofannealingtemperatureandtimeonthedeviceperformance.Itisfoundthatlongannealingat200℃isequivalenttoandevenoutperformsshortannealingat300℃.ExcellentelectricalcharacteristicsoftheTFTsaredemonstratedafterO_2annealingat200℃for35min,includingalowoff-currentof2.3×10~(-13)A,asmallsub-thresholdswingof245mV/dec,alargeon/offcurrentratioof7.6×10~8,andahighelectroneffectivemobilityof22.1cm~2/V·s.Undernegativegatebiasstressat—10V,theabovedevicesshowbetterelectricalstabilitiesthanthosepost-annealedat300℃.Thusthefabricatedhigh-performanceZnOTFTwithalowthermalbudgetisverypromisingforflexibleelectronicapplications.

  • 标签: 薄膜晶体管 退火温度 原子层沉积 通道 电特性 氧化铝