物理化学-王险峰（药学课件）电化学

物理化学-王险峰（药学课件）电化学内容摘要：

物理化学-王险峰（药学课件）电化学 Chaptet 5 Electrochemistty 电化学简史 第一阶段(1791一18833 年) 摩擦生电 感应生电现象: Volta 电池; Earaday 电解定律。 第二阶段 (1833一1905 年) 以热力学研究方法研究电化学平衡为主要特征。 蓄电池、王电池;Nernst 方程。 第三阶段(1905一 ) 以动力学方法研究电极过程为主要特征。 Tafel 公式 7一a十lnj/ji，Debye-Hiickel 离子互吸理论 了lectrochemistty Plays a dominant tole in a vastnumbet of teseatch and abblied ateas. This lsbasically a consequence of a unique combination ofdifferent featutes of electtrochemical teactions.By the apbblication of a botential they can ovetcomekinetic limitations even at vety low tempetatutes andate chetmically and even steteochetmically specific.This leads to apbplications to chemical Synthesis.These ate highly sensitive, even to exttemely smallamounts of teactants, leading to analyticalabplications. They may be limited to vety Specificand well-defined electrode sutface ateas with5-2 excejlent tembotal conttol of importance in theemetging field of nanotechnology. Electrochemicalreactions afe known for a wide tange of matetialsSuch as metals, semiconductots, polymets, andbiological systems. Electrochemisttry cuttently Plays alatge tole in a numbet of fathet divetrse ateas, Such asbtepatative chemistty, analytical chemistty, enefteyStoftage, enetgy convetsion, blochemistry, solid statechemistry, matetials science, and Imictoelecttonics.At the beginning of the fwentieth centuty，electrochemistty was mainly dominated by studies ofthe transbott of chatged spbecies and thetmodynamic5-3 considetations. With the bioneeting wotk cattied outby Butlet, Volmetr, Getischer, Matcus, and others，kinetic aspects of electrochemisttry have becomeImote imbottant in electrochemical teseatch since themiddle of the twentieth centuty with an incteasedundetstanding of the chemical and electtonicsttuctute of the solid/solution intetface. TheseStudies have been acceletated by the apblication ofnutmetous in-situ and ex-situ sbecttoscobpictechniques, which have been combined withelectrochemical expetiments ovet the last thitty yeats.More tecently the inttoduction of in-situ scanningbtobe techniques has allowed us to follow5-4 electrfochemical teactions on an atomic of molecularScale.Based on theotetical and exbetimental tesults andtmethods gatheted by electtrochemists for manydecades, electtochemistty is now used in manyfundamental fields, such as the study of new otganicand inotganic combounds and biological systems. Inmote apbblied ateas, it is used to shape matetials fomthe macrtoscoblic to the mictoscobic scale, toaccutately analyze for chemical imbutities, toundetstand and btevent the cottosion of matetials atlow and exttemely high tempetratutes, to btobe the5-5 function of living cells, and to convett chemicalenetgy into electticity.5S-6 第一节 电解质溶液的导电一、电解质深液的导电机理1电化学体系导体的类型第一类导体，即电子导体第二类导体，即离子导体 区 ， 携带 | 导电过程 电阻别闫别 电荷多宣 | 中反应“| 温度关系 电子导体 国 无 随温度上升 离子导体 | we 、we" | 电极反应 | 随温度下降 遇相符。 和 虹阻是电子的两 要是与声子碰撞;撞。 在室晕下，较纯净金属的内电子与杂质的础 类于撞引起的: 在纯净金属电子理论认为: 电阻与坎度的倒数成正比;子理论认为: 电阻与光度成正 比，与事实基本 在不纯 珊过 忆还要与杂质碰 撞对电阻的贡献不大, 只有在低温下杂质电阻才显现出来。