电化学石英晶体微天平研究高氯酸钠水溶液中活性炭电极的离子存储行为

以电化学石英晶体微天平(EQCM)为主要测试手段,在不同浓度的高氯酸钠(NaClO4)水溶液中研究了水合离子吸附到活性炭电极孔隙过程中电极的质量变化.对于每种电解液,根据Raman光谱和EQCM数据分别计算了本体溶液中和电极/溶液界面上Na+的水合数.通过比对这两组Na+水合数,探讨了Na+存储到活性炭负极过程中的去溶剂化效应.

Electrochemical Quartz Crystal Microbalance Studies on the Storage Behavior of Ions at Activated Carbon Electrodes in NaClO4 Aqueous Solutions

Electrochemical quartz crystal microbalance(EQCM) was used to study the mass changes on activated carbon electrodes in various NaClO4 aqueous solutions during the course of ions adsorption into the pores of the electrode. For each electrolyte solution, the hydration numbers of Na+ in the bulk solutions and at the electrode/solution interface were calculated from Raman and EQCM data, respectively. These two sets of hydration numbers of Na+ were compared and the desolvation effect of Na+ was investigated. Results indicate that the desolvation effect of Na+ is suppressed by increasing the concentrations of NaClO4 aqueous solutions, which may be one of the main reasons for the improvement of the supercapacitors' power density. At the same time, results also prove that EQCM is an excellent tool for studies on ions' adsorption.