电化学阻抗谱-基础知识

文档简介Electrochemicalimpedancespectroscopy(EIS)isapowerfultechniquethatutilizesasmallamplitude,alternatingcurrent(AC)signaltoprobetheimpedancecharacteristicsofacell.TheACsignalisscannedoverawiderangeoffrequenciestogenerateanimpedancespectrumfortheelectrochemicalcellundertest.EISdiffersfromdirectcurrent(DC)techniquesinthatitallowsthestudyofcapacitive,inductive,anddiffusionprocessestakingplaceintheelectrochemicalcell.ThetheorybehindEISismorecomplexthanDCtechniques,soit’sadvisedtohaveabasicunderstandingoftheunderlyingprinciplesbeforebeginning.EIShasfarreachingapplicationsincludingcoatings,batteries,fuelcells,photovoltaics,sensors,andbiochemistry.ThisguidewillfocusontheapplicationoftheEIStechniqueforanalyzingthecorrosionperformanceofcoatedaluminumpanel.Knowledgeoftheelectrochemicalsystembeinginvestigatedisalsousefulbeforebeginning.Withabasicunderstandingofthesystemitcanbeknownifthepotentiostatwillbeabletogatherthedesiredinformation,andifthedatacollectedmeetsaccuracyrequirements.