SnO2修饰石墨毡电极的制备及其性能表征

采用H₂O₂对石墨毡（GF）进行预处理，然后在其表面电沉积Sn，最后在120℃烘箱氧化24 h制备出SnO₂修饰的石墨毡电极。通过扫描电镜（SEM）对SnO₂修饰前后的石墨毡表面形貌进行表征，采用循环伏安法研究了SnO₂修饰后石墨毡电极的电化学性能。结果表明：SnO₂能够均匀地包覆在石墨毡表面；SnO₂修饰石墨毡后V⁴⁺/V⁵⁺电对的氧化峰的峰电流由0.0538 A增加到0.0708 A，与未处理石墨毡相比增加了31.5%，反应峰出峰持续时间提高，说明SnO₂对V⁴⁺/V⁵⁺电对电极过程具有一定的催化作用。析氧电位由1.382 V增加到了1.517 V，使电极在VOSO₄溶液中的电化学窗口变宽。

Preparation and characterization of the modified graphite felt electrode by SnO2

The graphite felt (GF) was pretreated with H₂O₂, and then Sn was electrodeposited on pretreated GF. At last, the SnO₂ modified GF was obtained by oxidation of Sn at 120℃ for 24 h. The morphologies of GF before and after modified by SnO₂ were characterized by SEM, and the electrochemical properties of GF modified by SnO₂ were investigated by cyclic voltammogram. The results show that the SnO₂ coating is uniformly formed on the surface of GF. The oxidation peak current increases from 0.053 8 A to 0.070 8 A, which means 31.5% improves before and after SnO₂ modification of GF. The duration time of oxidation enhances after SnO₂ modified, which indicates that SnO₂ performs a catalytic action upon the reaction of vanadium ions. In addition, the potential of oxygen evolution increases from 1.382 V to 1.517 V. Therefore, the electrochemical window of GF electrode in VOSO₄ solution is widened by modification of SnO₂.