【摘要】 以Fe(Ⅲ)/Fe(Ⅱ)为正极电解液的氧化还原电池,用循环伏安、交流阻抗、充放电等方法研究了在硫酸体系中的电化学行为。结果显示,Fe(Ⅲ)/Fe(Ⅱ)反应是准可逆过程,当硫酸的浓度为0.50 mol/L时,峰电流最大,Fe(Ⅱ)扩散系数Dc为2.276×10-6cm2/s;在0.37 V下的电化学极化阻抗为2.238Ω/cm2;与锌溶液组成电池,在20 mA/cm2进行循环充放电,充电电压在1.65~1.72 V,放电电压在1.11~1.25 V,电流效率为80%~97%,电压效率为65%~75%,能持续稳定循环110次。更多还原

【Abstract】 The redox flow cell in which Fe( Ⅲ) /Fe( Ⅱ) was used as athodic electrolyte,the electrochemical behaviour of redox reaction of Fe( Ⅲ) / Fe( Ⅱ) in sulfuric acid was investigated by means of cyclic voltammetry,impedance spectroscopies and charge-discharge. Result indicated that Fe( Ⅲ) / Fe( Ⅱ) redox reaction was quasi reversible. The diffusion coefficient for Fe( Ⅱ) was 2. 276 × 10-6cm2/ s,the electrochemical impedance was 2. 238 Ω / cm2under 0. 37 V. A Zn-Fe battery was assemble with Fe( Ⅲ) / Fe( Ⅱ)-sulfuric acid positive species and Zn/Zn( Ⅱ)-methanesulfonic acid negative species. The cell voltage in charged state was 1. 65 ~ 1. 72 V and discharge voltage reached up to 1. 11 ~ 1. 25 V. The coulombic and voltage efficiency were 80% ~ 97% and 65% ~ 75%,and it showed a good cyclic charge-discharge performance,which indicates that ferrous sulfate has a promise application prospect in redox flow cell.更多还原