应用电化学循环伏安和石英晶体微天平(EQCM)方法研究了0.1mol·L-1硫酸溶液中Pt电极表面的吸附和氧化过程.从电极表面质量变化的结果分析,可认为正向电位扫描时氢区表面质量的增加是由于水分子取代Had引起的,而双电层区的质量增加则是由于水的吸附模式逐渐由氢端吸附转向氧端吸附所致.根据频率变化和电量数据,进一步推算出水在双电层区是以低放电吸附形式出现的,1molPt原子和水分子只发生0.054mol的电荷转移.本文结果可为认识Pt电极表面过程提供定量的新数据.
Simultaneous frequency and current responses during potential cycling of Pt electrode were measured in 0.1 mol·L-1 H2SO4 solution by using EQCM.Quantitative analysis of the mass change revealed that the increase of mass in the hydrogen and double_layer regions in a positive_going potential scan was due to water adsorption on the Pt electrode,further calculation indicated that water molecules adsorbed on Pt electrode in the double_layer regions through a low discharge quomodo .The EQCM studies provided quantitative results of surface mass variation during water adsorption and oxidation,and have thrown new light in elucidating the structure of double_layer between electrode and solution.
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