鎳基電極的組成與結構調控及性能優(yōu)化摘要：

隨著電化學領域的發(fā)展，鎳基電極在電化學能源儲存、電解水制氫和電催化反應等方面已經得到了廣泛的應用。然而，電化學活性和穩(wěn)定性等方面的性能優(yōu)化仍面臨許多挑戰(zhàn)，這也使得鎳基電極材料成為了當前研究熱點領域之一。本文主要探討了鎳基電極的組成與結構調控及性能優(yōu)化方面的研究現(xiàn)狀與進展。首先，介紹了鎳基電極的基本組成、電化學性質和性能要求。然后，重點介紹了近年來在組成與結構調控方面的一系列研究進展，涵蓋了各種化學合成方法、結構調控策略和表面改性等方面的研究成果，并分析了這些研究成果對鎳基電極性能優(yōu)化的影響。最后，對未來鎳基電極研究方向和重要挑戰(zhàn)進行展望。

關鍵詞：鎳基電極；組成；結構調控；性能優(yōu)化；電化學儲能；制氫；電催化反應。

1.引言

電化學能源儲存、電解水制氫和電催化反應等領域需要高效穩(wěn)定的電極材料。鎳基電極作為一種重要的電極材料，在電化學儲能、制氫和電催化反應等方面已經得到了廣泛的應用[1-3]。然而，鎳基電極還存在著一些挑戰(zhàn)，比如，低活性、低穩(wěn)定性和低機械強度等[4-5]。因此，對鎳基電極的組成和結構進行調控，以提高其電化學活性和穩(wěn)定性等性能指標，已成為當前重要的研究熱點之一。

2.鎳基電極的基本組成和性能需求

鎳基電極的基本組成包括基底材料、活性層材料和導電劑等[6]。其中，基底材料通常是金屬，如不銹鋼，活性層材料則是鎳及其合金，導電劑則是碳材料或其他電導材料[7]。鎳基電極的電化學性質取決于其化學組成、形態(tài)和結構等因素[8-10]，如化學組成可以影響活性層的表面電荷分布和電子能級結構等性質；形態(tài)和結構可以影響活性層的分散、可達性和穩(wěn)定性等方面。

鎳基電極的性能需求主要包括以下幾個方面[11]：

(1)高電化學活性和穩(wěn)定性，以實現(xiàn)高效的電化學反應過程；

(2)低電阻和高導電性能，以降低電極反應極化，提高電化學反應效率；

(3)良好的機械強度和穩(wěn)定性，以保證電極材料能夠長期穩(wěn)定工作。

3.鎳基電極組成與結構調控策略

針對上述性能需求，通過設計合理的組成和結構，可以實現(xiàn)鎳基電極材料的性能優(yōu)化。下面我們將就鎳基電極的組成與結構調控兩方面進行闡述：

3.1組成調控策略

鎳基電極活性層的組成對其電化學性能具有重要影響[12]。在鎳基電極活性層中，材料的種類、尺寸和表面形貌等因素都將直接影響其電化學活性和穩(wěn)定性。近年來，通過合理調控組成，可以實現(xiàn)電化學儲能、電解水制氫、電催化減除有機物等領域的重大突破，其中包括以下方面：

(1)合成鎳基納米顆粒材料

納米顆粒材料具有較高的比表面積，活性層中添加納米材料可以增強鎳基電極的電化學活性[13]。通過一種尿素-熱解法制備的氮摻雜有序多孔碳/鎳納米顆粒對電化學儲能和電解水制氫等方面表現(xiàn)出較好表現(xiàn)[14-15]。

(2)合成鎳基合金材料

比如，通過將Ni-Co合金封裝到碳納米管中可以獲得高比表面積的Ni-Co/CNTs催化劑，表現(xiàn)出較好的電化學儲能和電解水制氫性能[16]。

(3)催化劑包覆或修飾

在鎳基電極活性層上包覆或修改成其他催化劑可以增強其電化學催化活性。這種方式可以在催化反應中提供協(xié)同作用[17]。

3.2結構調控策略

鎳基電極活性層的結構也對其性能具有重要影響。材料的晶粒尺寸、分散性和表面形貌等因素都將直接影響其電化學活性和穩(wěn)定性[18]。在結構調控方面，包括以下策略：

(1)控制晶粒尺寸

通過控制材料合成過程中的反應條件和添加不同外加劑等手段，調控晶粒的尺寸和形態(tài)可以影響電極的電化學活性和穩(wěn)定性。比如，通過不同方法控制多孔碳材料的孔徑和孔隙度可以影響催化劑的形態(tài)和分散度，從而影響電極的電化學性能[19]。

(2)界面調控

可通過表面改性方式調控鎳基活性層材料的化學/物理特性，如改變表面電荷分布和電子能級結構，以增強電極的電化學反應活性[20-21]。

(3)表面修飾

在鎳基電極活性層表面修飾一層穩(wěn)定劑材料，可以提高催化劑的穩(wěn)定性和電化學活性等性能，從而有助于延長電極材料的使用壽命和提高催化效率[22]。

4.鎳基電極性能優(yōu)化

通過調控鎳基電極的組成和結構，可以明顯提高其電化學活性和穩(wěn)定性等性能指標。然而，鎳基電極材料性能優(yōu)化仍面臨許多挑戰(zhàn)，包括：

(1)結構的分級調控

結構分級的進一步調控可以進一步提高鎳基電極材料的電化學活性和穩(wěn)定性。但對于多種合成方式和處理工藝條件的選擇，如何形成合適的結構分級仍需研究。

(2)深入了解鎳基電極催化機理

針對涉及催化機理和電極反應機理的問題，尤其是催化劑活性中心和反應位點，需要進行進一步的研究。

(3)進一步完善性能評價體系

發(fā)展一套適用于不同電化學應用場景的性能評價體系，能夠更全面、準確地評估鎳基電極材料的性能。

5.結論

近年來，通過對鎳基電極的組成和結構進行調控，不斷優(yōu)化其電化學性能已成為研究熱點之一。鎳基電極材料的優(yōu)化設計，涵蓋了各種化學合成方法、結構調控策略和表面改性等方面的研究。但仍面臨很多挑戰(zhàn)，包括結構的分級調控、深入了解催化機理和電極反應機理和完善性能評價體系等。未來，我們需要深入研究鎳基電極的組成和結構調控方面，以滿足不同電化學應用場景的需求。

關鍵詞：鎳基電極；組成；結構調控；性能優(yōu)化；電化學儲能；制氫；電催化反應。

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[9]JongPilKim,Hee-YoungKim,IshfaqAhmad,etal.Effectsofsurfacecharacteristicsonelectrocatalyticactivityofnickel-basedcatalystsforthehydrogenevolutionreaction[J].JournalNickel-basedmaterialsarewidelyusedaselectrodesforvariouselectrochemicalreactions,includingelectrolysis,fuelcells,andammoniasynthesis.Thepropertiesandelectrochemicalperformanceofnickel-basedelectrodesarestronglyinfluencedbythedepositionconditionsandtheresultingmicrostructure.Forexample,electrodepositionparameterssuchascurrentdensity,pH,andtemperaturecanaffectthecrystallinestructure,porosity,andsurfacemorphologyofnickelfilms.Thesurfacecharacteristicsofnickel-basedelectrodes,includingtheirchemicalcomposition,crystalorientation,andsurfacearea,alsoplayacrucialroleindeterminingtheirelectrocatalyticactivity.

Inrecentyears,considerableresearcheffortshavebeendedicatedtoimprovingtheperformanceofnickel-basedelectrodesforammoniasynthesis.Oneofthekeychallengesinelectrochemicallydrivenammoniasynthesisistodevelopanefficientandstableelectrocatalystthatcanfacilitatetheconversionofnitrogenandhydrogenintoammonia.Nickel-basedelectrodeshavebeenshowntoexhibitexcellentelectrocatalyticactivityforammoniasynthesis,owingtotheirhighsurfacearea,highconductivity,andgooddurability.However,thepropertiesofnickel-basedelectrodescanvarysignificantlydependingonthedepositionconditionsandthepost-treatmentprocesses.

Studieshaveshownthatnickel-basedelectrodeswithahighsurfaceareaandauniformmorphologycanenhancetheelectrochemicalperformanceforammoniasynthesis.Toimprovetheelectrocatalyticactivityofnickel-basedelectrodes,severalstrategieshavebeenproposed,includingtheuseofnanostructurednickelfilms,theincorporationofothermetals,suchascobaltandmolybdenum,andthemodificationofthesurfacewithfunctionalgroupsorcatalysts.Additionally,theuseofspecificelectrolytesandreactionconditionscanalsoimprovetheperformanceofnickel-basedelectrodes.

Insummary,nickel-basedelectrodesarepromisingmaterialsforvariouselectrochemicalreactions,includingammoniasynthesis.Theelectrochemicalperformanceofnickel-basedelectrodesisstronglyinfluencedbytheirdepositionconditionsandsurfacecharacteristics,whichcanbetailoredtoenhancetheirelectrocatalyticactivity.Furtherresearchisneededtoinvestigatethemechanismsunderlyingtheelectrochemicalreactionsonnickel-basedelectrodesandtodevelopnewstrategiesforimprovingtheirperformance.Anotherimportantfactoraffectingtheelectrochemicalperformanceofnickel-basedelectrodesistheirstabilityovertime.Theexposuretoreactivegasesorhightemperaturescancausedegradationoftheelectrodesurface,leadingtoadecreaseinitselectrocatalyticactivity.Inaddition,theinteractionofnickelwithotherelements,suchasoxygenornitrogen,canaffectitselectronicpropertiesandalteritsreactivitytowardsdifferentelectrochemicalreactions.

Toovercomethesechallenges,differentstrategieshavebeenproposedtoimprovethestabilityandperformanceofnickel-basedelectrodes.Forinstance,theuseofprotectivecoatingsorsurfacemodificationscanenhancetheirresistanceagainstdegradationandprolongtheirlifespan.Moreover,thedesignofnovelnanostructuredmaterials,suchasnickelnanoparticlesornanowires,canfurtherincreasetheirsurfaceareaandpromotetheircatalyticproperties.

Anotherimportantareaofresearchfocusesontheoptimizationoftheoperatingconditionsforelectrochemicalreactionsusingnickel-basedelectrodes.Theperformanceofelectrocatalyticprocessesstronglydependsonfactorssuchastemperature,pressure,pH,andreactantconcentration,amongothers.Therefore,theselectionofoptimaloperatingconditionscansignificantlyimprovetheefficiencyandselectivityofelectrochemicalreactions.

Insummary,nickel-basedelectrodesareversatilematerialswithgreatpotentialforelectrochemicalreactions,includingammoniasynthesis.Theirelectrocatalyticactivitycanbetailoredbycontrollingtheirdepositionconditions,surfacecharacteristics,andoperatingconditions.However,furtherresearchisneededtoaddressthechallengesassociatedwiththeirstability,reactivity,andefficiency,andtoexplorenewstrategiesfortheirimprovement.Oneofthemajorchallengesinusingnickel-basedelectrodesforelectrochemicalreactions,includingammoniasynthesis,istheirstabilityovertime.Nickelissusceptibletooxidationandcorrosion,whichcanhinderitscatalyticperformanceandshortenthelifespanoftheelectrode.Therefore,itisimportanttodesignelectrodematerialsthatareresistanttooxidationandcorrosion,ortodevelopprotectivecoatingsthatcanpreventtheseprocessesfromoccurring.Forinstance,someresearchershaveinvestigatedtheuseofgrapheneorcarbon-basedcoatingstoenhancethestabilityofnickelelectrodes,duetotheirhighconductivity,stability,andchemicalinertness.

Anotherchallengeistooptimizethereactivityandselectivityofnickel-basedelectrodesforspecificelectrochemicalreactions.Dependingonthereactionconditionsandtheelectrodeproperties,nickelcanexhibitdifferentelectrocatalyticactivitytowardsvariousmolecules,suchashydrogen,nitrogen,orcarbondioxide.Therefore,itiscrucialtounderstandthemechanismsoftheelectrochemicalreactionsandtooptimizetheelectrodepropertiesandoperatingconditionsaccordingly.Forexample,someresearchershavestudiedtheeffectofsurfacedefects,crystalorientation,andnanoparticlesizeontheelectrocatalyticactivityofnickel,aimingtoimproveitsselectivityandefficiencytowardsammoniaproduction.

Moreover,theefficiencyofnickel-basedelectrodesforelectrochemicalreactionsisalsoaffectedbytheenergyconsumptionandtheoverallcostoftheprocess.Electrochemicalreactionsusuallyrequireanexternalpowersource,andtheenergyefficiencyoftheprocessisdeterminedbytherateofelectrontransferandtheoverpotentialrequiredtodrivethereaction.Therefore,itisimportanttodevelopelectrodematerialsandsystemsthatcanminimizetheenergyconsumptionandthecostoftheprocess.Forinstance,someresearchershaveexploredtheuseofrenewableenergysources,suchassolarorwindpower,todriveelectrochemicalreactions,andhaveintegratedtheelectrodematerialsintooptimizedreactordesignstoimprovetheoverallperformance.

Finally,tofullyexploitthepotentialofnickel-basedelectrodesforelectrochemicalreactions,itisimportanttoexplorenewstrategiesforelectrodedesignandsynthesis.Forexample,someresearchershaveinvestigatedtheuseofhierarchicalorporousstructurestoincreasethesurfaceareaandtheaccessibilityofactivesitesontheelectrodesurface,aimingtoenhancethecatalyticperformanceofnickel.Othershaveexploredtheuseofhybridmaterialsorcompositestructures,combiningnickelwithothermetalsorfunctionalmaterials,tosynergisticallyenhancetheelectrocatalyticactivityandselectivity.

Inconclusion,nickel-basedelectrodeshaveshowngreatpotentialforawiderangeofelectrochemicalreactions,includingammoniasynthesis.However,furtherresearchisneededtoovercomethechallengesassociatedwiththeirstability,reactivity,efficiency,andcost,andtoexplorenewstrategiesfortheiroptimizationandimprovement.Withcontinuedeffortsandinnovations,nickel-basedelectrodescouldbecomeatransformativetechnologyforsustainableandefficientenergyproductionandstorage,aswellasforthesynthesisofvaluablechemicalsandmaterials.Oneofthemainchallengesinusingnickel-basedelectrodesforelectrochemicalreactionsistheirstability.Nickelissusceptibletocorrosion,especiallyinacidicandalkalineenvironments.Thiscanresultinthedegradationoftheelectrode,leadingtodecreasedefficiencyandeffectivenessovertime.Toovercomethischallenge,researchersareexploringmethodstoenhancethestabilityanddurabilityofnickel-basedelectrodes.Forexample,theyareinvestigatingnewelectrodedesignsandcoatingsthatcanprotectthenickelsurfacefromcorrosionandextendtheelectrode'slifespan.

Anotherchallengeisreactivity.Nickelhasarelativelylowreactivitycomparedtoothermetals,suchasplatinumandgold,whichareoftenusedascatalystsinelectrochemicalreactions.Toimprovethereactivityofnickel-basedelectrodes,researchersareexploringwaystomodifythesurfaceoftheelectrodeandenhanceitscatalyticproperties.Thisincludesusingnanostructuredmaterialsorintroducingdopantsthatcanincreasethesurfaceareaandpromotemoreactivesitesforthereaction.

Efficiencyisalsoakeyconsiderationfornickel-basedelectrodes.Whilenickelisabundantandrelativelylow-cost,itisnotasefficientasothermetalsincatalyzingcertainelectrochemicalreactions.Therefore,researchersareexploringwaystoboosttheefficiencyofnickel-basedelectrodesbyoptimizingtheircomposition,structure,andoperatingconditions.Forexample,theyareinvestigatingwaystoenhancethemasstransportofreactantsandproductstoandfromtheelectrodesurface,aswellasexploringnewreactionpathwaysthatcanmaximizetheyieldandselectivityofthedesiredproducts.

Finally,costisacriticalfactorinthedevelopmentofnickel-basedelectrodesforsustainableenergyandchemicalproduction.Whilenickelisabundantandlow-costcomparedtoothermetals,theoverallcostoftheelectrodealsodependsonotherfactors,suchasprocessingandmanufacturingcosts,aswellastheoverallsystemdesignandintegration.Toaddressthischallenge,researchersareexploringnewmanufacturingmethodsandmaterialsthatcanreducetheoverallcostofnickel-basedelectrodes,suchasusinglow-costprecursorsordevelopingscalableandcost-effectiveelectroplatingtechniques.

Inconclusion,nickel-basedelectrodeshavethepotentialtorevolutionizethefieldofelectrochemistryandenablesustainableandefficientenergyandchemicalproduction.However,significantchallengesremainregardingtheirstability,reactivity,efficiency,andcost.Withcontinuedresearchandinnovation,itispossibletoovercomethesechallengesandunlockthefullpotentialofnickel-basedelectrodesforamoresustainablefuture.Oneareaofresearchthatcouldpotentiallyenhancetheperformanceofnickel-basedelectrodesisthedevelopmentofnewcatalyststhatcanimprovetheirelectrocatalyticactivity.Thesecatalystscouldincreasetherateoftheelectrochemicalreactionsthatoccurattheelectrodesurface,leadingtofasterandmoreefficientenergyconversion.Onepromisingcatalystforthispurposeisgraphene,atwo-dimensionalmaterialthathasexceptionalelectronicandmechanicalproperties.

Researchershavealreadydemonstratedthatgraphene-basedcoatingscansignificantlyenhancetheelectrocatalyticactivityofnickelelectrodesbyincreasingtheirsurfaceareaandfacilitatingfastchargetransfer.Forexample,arecentstudyfoundthatanickelelectrodecoatedwithathinlayerofgrapheneoxideexhibitedmorethantwicetheelectrocatalyticactivityofanuncoatedelectrodeintheoxidationofmethanol.

Anotherareaofresearchthatcouldimprovetheperformanceofnickel-basedelectrodesisthedesignofnewelectrodearchitecturesthatcanenhancetheirstabilityanddurability.Onepromisingapproachistheuseofnanostructuredmaterials,whichcanprovideahighsurfacearea-to-volumeratioandallowforefficienttransportofreactantsandproductswithintheelectrode.

Forexample,researchershavedevelopednickelnanowirearraysthatexhibithighstabilityandelectrochemicalactivityforenergystorageandconversionapplications.Thesenanowirearrayshavealargeeffectivesurfaceareaandcanundergorepeatedcyclesofcharginganddischargingwithoutsignificantdegradation.

Overall,thedevelopmentofnewcatalystsandelectrodearchitecturesisexpectedtoplayanimportantroleinimprovingtheperformanceofnickel-basedelectrodesforsustainableenergyandchemicalproduction.Additionally,continuedresearchintothefundamentalprinciplesgoverningthebehavioroftheseelectrodescouldleadtonewinsightsandbreakthroughsinthefieldofelectrochemistry.Otherfactorsthatmayimpacttheperformanceandsustainabilityofnickel-basedelectrodesincludethesourceandavailabilityofrawmaterials,aswellaspotentialenvironmentalandhealthconcernsassociatedwiththeirproductionanduse.Forexample,nickelminingandrefiningcanhavenegativeenvironmentalimpactssuchassoil