恒电位氧化改性石墨毡及其氧还原电极的电化学性能（英文）

Electrochemical Performance of Graphite Felts Modified by Potentiostatic Oxidization for Oxygen Reduction Cathode

分别采用循环伏安改性法和恒电位氧化法对石墨毡进行改性处理,并采用循环伏安法对其电化学性能进行研究,实验结果表明,恒电位氧化改性较循环伏安改性的石墨毡有较好的氧还原活性。通过XRD、FTIR、接触角和CV针对恒电位氧化处理石墨毡进行了进一步的测试。测试结果显示,随恒电位氧化时间的增加,石墨毡表面亲水性含氧官能团增加,润湿性增强。恒电位氧化改性处理25 min的石墨毡氧还原峰电位及电流密度分别为^-0.43 V和~0.003 4 m A·cm^(-2),显示出很好的电化学催化性能。基于以上结果,恒电位氧化法改性处理能够极大提高石墨毡的氧阴极活性。

The graphite felts were respectively modified by cyclic voltammetry （CV）and potentiostatic oxidation （PO）, which electrochemical performances were evaluated by cyclic voltammetric experiments. As a result, PO modification is more effective on improving the oxygen reduction reaction （ORR）activity of the graphite felts than CV treatment. The PO modified graphite felts were further investigated by XRD, FTIR, Contact angle and CV. It is found that the wettability of the graphite felts increases with the increase of potentiostatic oxidation time, due to the increase of the hydrophilic oxygen-containing functional groups on surface. The graphite felt modified by PO for 25 min in this work exhibits the preferable electrochemical performances with the reduction potential ^-0.43 V and the current density ~0.003 4 mA·cm^-2 of the reduction peak on CV curve. Consequently, potentiostatic oxidation is an effective and feasible treatment for improving the electrochemical properties of the graphite felts as the electrode material of Li-O2 batteries.