IrO_2纳米棒的制备及电化学性能

Preparation and electrochemical performance of IrO_2 nanorods

在惰性气氛条件下，以IrCl 3？nH 2 O为原料，通过溶胶？凝胶法制备纳米棒IrO 2催化剂。采用X射线衍射、透射电子显微镜和电化学性能测试分别对所得催化剂样品的物相组成、形貌结构和电化学性能进行表征。XRD结果显示，催化剂样品IrO 2是直径为10~20 nm、长度约为90 nm的金红石型纳米棒状单晶氧化物。循环伏安测试表明，电极电势低于0.3 V或高于1.2 V时催化剂表面发生水的电解反应，而电极电势约为0.83 V时催化活性中心离子对（Ir（III）/Ir（IV））发生自身氧化还原反应。线性扫描电势测试表明，所制备 IrO 2纳米棒催化剂的析氧电催化活性高于商业IrO 2催化剂的析氧电催化活性，且当电极电势为1.7 V时其析氧电催化活性约是商业催化剂析氧电催化活性的1.38倍。

IrO 2 nano-rod catalysts were prepared using IrCl 3？nH 2 O as raw material by sol？gel method under inert atmosphere. Their phase composition, morphology and electrochemical performance were characterized by X-ray diffractometry, transmission electron microscopy and electrochemical properties test techniques, respectively. The result of XRD indicates that the catalyst sample IrO 2 is a single crystal nanorod rutile oxide with a diameter in the range of 10？20 nm and a length of around 90 nm. The results of cyclic voltammetries show that, when the electrode potential is lower than 0.3 V or higher than 1.2 V, a water electrolysis reaction can be detected on the catalyst samples. The transforming process of catalytic activity center ion pair Ir（III）/Ir（IV） takes place at electrode potential of about 0.83 V. Finally, linear sweep voltammetry reveals that the oxygen evolution reaction catalytic activity of IrO 2 nanorods is superior to that of the commercial IrO 2 catalysts, which is about 1.38 times as much as that of the commercial catalysts at electrode potential of about 1.7 V.