溶胶-凝胶论文：溶胶—凝胶与纳米材料修饰电极及其电化学性质

溶胶-凝胶论文溶胶—凝胶与纳米材料修饰电极及其电化学性质【中文摘要】近年发展起来的溶胶-凝胶技术其载体为无机多孔材料具有许多高分子无法比拟的特性为纳米材料的固定提供了更广阔的空间纳米材料具有比表面积大、催化活性高、亲和力强等特点在电催化及传感器材料领域有着广阔的应用前景研究表明电化学过程与电极材料的表面性质密切相关由于该材料的尺寸效应和介电限域效应等特性将纳米材料修饰到电极表面能增加电流响应降低检测限大大提高检测的灵敏度本论文致力于溶胶-凝胶与纳米材料修饰电极的制备及其电催化性能的研究修饰电极过程简单、方便实现了将溶胶-凝胶、纳米材料、修饰电极和电分析化学的有机结合主要工作如下:

1.3-氨丙基三乙氧基硅烷单层修饰电极及其表面非均相扩散:铂纳米花的形成及其电催化性质3-氨丙基三乙氧基硅烷在铂电极表面形成单层修饰膜诱导铂纳米花在其表面形成我们通过场发射扫描电镜、X-粉末衍射和电化学方法表征了得到的铂纳米花的性能本工作细致探讨了铂纳米花的生长机理可能的解释是PtCl62-离子在铂电极表面的不均匀扩散我们还发现铂纳米花修饰电极比铂纳米修饰电极对甲醇的氧化和氧气的【英文摘要】Recentlysol-gel-basednanomaterialsanddeviceshavebeenextensivelyappliedinallkindsoffieldsduetotheirporousstructuregoodmechanicalstrengthandlong-termstability.Itiswell-knownthattheelectrochemicalresponsesofmodificationelectrodesarerelatedtotheelectrodematerials.Currentresponsecanbeimprovedanddetectionlimitcanbeextendedwhenthenanomaterialsmodifiedelectrodesareemployed.Themainworkofthispaperisfocusonpreparationofsol–gel-basedmaterialsandnovelnanomaterialsmodifiedelectrodeswhichhavebeenusedtoinvestigatetheelectrocatalyticproperties.Comparedwiththetraditionalelectrodesthemodificationprocessissimpleandconvenient.Moreovertheaboveproposedelectrodeshavebeenusedtodetectandanalysizesomeanalystssuchasmethanoloxygenandhydrogenperoxide.Thedetailsarelistedbelow:

1.InhomogeneousDiffusiononElectrodeSurfaceInducedby（3-Aminopropyl）triethoxysilaneMonolayer:theFormationofPtNanoflowersanditsElectrocatalysisHierarchicalflowerlikePt（PtnanoflowersPtNFs）nanostructureshavebeenformedonthesurfaceofPtelectrodeinducedby3-aminopropyltriethoxysilane（APTES）monolayer.ScanningelectronmicroscopyX-raypowderdiffractionandelectrochemicalmethodshavebeenusedtocharacterizethepropertiesoftheseobtainedPtNFs.ThegrowthmechanismofthePtNFshasbeendiscussedcarefullywhichmaybeduetotheinhomogeneousdiffusionofPtCl62-ionsonthesurfaceofPtelectrode.IthasbeenfoundthatthePtNFsmodifiedelectrodesexhibitexcellentelectrocatalyticactivitytowardstheoxidationofmethanolandthereductionofoxygencomparedtoPtnanoparticlesmodifiedelectrodes.TheincreasedcatalyticactivitymaybearesultoftheuniquemorphologyofthePtNFs.

2.Electrochemicallydepositedsol-gel-derivedsilicatefilmsandtheelectrochemicalpropertiesofporeelectrodeSolgel-derivedsilicatefilmswereelectrochemicallydepositedonconductivesurfacesfromasolconsistingoftetramethoxysilane（TMOS）.InthismethodasufficientlynegativepotentialisappliedtotheelectrodesurfacetoreduceoxygentohydroxylionswhichservesasthecatalystforthehydrolysisandcondensationofTMOS.Theelectrodepositedfilmswerecharacterizedfortheirsurfacemorphologyelectrochemicalprobetechniques.Theelectrodepositedfilmswerefoundtohaveacompletelydifferentsurfacestructureandtobesignificantlyrougherrelativetospin-coatedfilms.Thisislikelydueinparttotheseparationofthegelationandevaporationstagesoffilmformation.TheporeelectrodewasfabricatedbyelectrodepositedinnegativepotentialwhichwascharacterizedbyScanningelectronmicroscopyandelectrochemicalmethods.Theelectrodewasappliedinbiosensorfields.

3.ElectrochemicalsynthesisAu@PtnanoparticlesoncholinechloridemodifiedglassycarbonelectrodeforsensitivedetectionhydrogenperoxideAsimpleelectrochemicalsensorforsensitivedeterminationofhydrogenperoxidewasfabricatedbyelectrochemicalsynthesisofAu@Ptnanoparticles（core@shell）onthesurfaceofcholinechloride（Ch）modifiedglassycarbonelectrode（GCE）.ChwasusedtocombinemetalionsandalsoplayedadualroleofstabilizerintheconstructionofAu@Ptnanoparticles.AunanoparticleswasimmobilizedontheChbyunderpotentialelectrodeposition（UPD）process.Aone-atom-thickshellofCuwasmodifiedontheAucorebyelectrochemicalunderpotentialdepositionandthenthismodifiedelectrodewasputintoH2PtCl6solutiontheCumonolayerwasreplacedwithPtbygalvanicexchange.TheobtainedAu@Ptnanoparticleswerecharacterizedbyscanningelectronmicroscope（FE-SEM）andelectrochemicaltechniques.AsaresulttheAu@Pt（core@shell）exhibitedremarkableelectrocatalyticactivitytowardsthereductionofhydrogenperoxide.UndertheoptimumconditionsChronoamperometricexperimentsshowedthatatanappliedpotentialof10mV（AgCl）thereductioncurrentofH2O2waslineartoitsconcentrationintherangeof32uMto

2.496mMandalowdetectionlimitof

1.0×10-6Mthepromisingelectrochemicalsensorwasinvestigatedagainstascorbicacid（AA）anduricacid（UA）theresultsdemonstratedthatthesensorexhibitedstabilityrepeatabilityandselectivity.【关键词】溶胶-凝胶纳米材料修饰电极电催化【英文关键词】sol-gelnanomaterialsmodifiedelectrodeelectrocatalysis【目录】溶胶—凝胶与纳米材料修饰电极及其电化学性质摘要5-7ABSTRACT7-9第一章综述11-

201.1溶胶-凝胶的制备、性质及应用11-

121.2纳米粒子制备、性质及应用12-

161.3双金属核-壳结构纳米复合电极的构建

161.4本论文的研究目的和设想16-17参考文献17-20第二章3-氨丙基三乙氧基硅烷单层在电极表面非均相散:铂纳米花的形成及其电催化性质20-

392.1前言20-

212.2实验部分21-

222.3结果与讨论22-

342.4结论34-35参考文献35-39第三章电化学沉积四甲氧基硅烷膜孔状电极及其电化学性质39-

483.1前言39-

403.2实验部分40-

413.3结果与讨论41-

473.4结论47参考文献47-48第四章在胆碱修饰的玻碳电极上电化学合成Aucore@Ptshell纳米粒子用于双氧水的检测48-

594.1前言48-

494.2实验部分49-

504.3结果与讨论50-

574.4实验结论57参考文献57-59工作展望59-60附录研究生期间发表论文及获奖情况60-61致谢61。