摘要
The kinetics of electrode reaction was investigated by cyclic voltammetry,and cyclic voltammograms show that the reversibility of the Fe(bpy)3^2+/Fe(bpy)^3+electrode reaction is better than that of the Zn/Zn^2+electrode reaction on the graphite disc.However,the Fe(bpy)3^2+ion diffusion in electrolyte is subject to greater resistance than that of the Zn^2+ion one.The stability of the Fe(bpy)3Cl2 solution was investigated by UV-vis spectroscopy,and the performance of a mild redox flow battery employing ZnCl2 and Fe(bpy)3Cl2 in the NaCl aqueous solution with various membranes as the separator was also investigated.It was found that the Celgard 3501 membrane cannot effectively prevent Fe(bpy)3^2+ions from leaking into anolyte,leading to the rapid failure of the flow battery.Although the Nafion 115 membrane can be polluted by Fe(bpy)32+ions,it is not invalidated.The Nafion 115 membrane shows good selectivity,which can avoid Fe(bpy)32 ions from leakage into anolyte.The ZnCl2/Fe(bpy)3Cl2 flow battery with the Nafion 115 membrane exhibits the capacity retention of 80%after 200 cycles.
基金
supported by the National Natural Science Foundation of China(Grant No.21361010)
the Natural Science Foundation of Jiangxi Province(20171BAB206001)
the Education Department of Jiangxi Province(GJJ190433)
the China Scholarship Council(201708360025)。
