电解煤浆制氢阳极的制备及电催化活性研究

将钛片进行预处理, 用处理后的钛片作为电极基体, 然后用循环伏安法在钛基体上沉积制备了Pt/Ti, Pt-Ru/Ti, Pt-Ir/Ti, Pt-Ru-Ir/Ti催化电极, 通过扫描电镜(SEM)、X射线衍射(XRD)、电子能谱(EDS)以及等离子发射光谱(ICP)等方法对所制备电极进行了表征, 包括电极表面形貌、组分的沉积状态、催化层成分组成以及电极寿命等; 在煤浆电解过程中, 采用两电极体系, 对所制备电极的电催化活性进行了测试. 结果表明: 所制备的电极催化活性都高于同面积的铂片电极, 含有Ru, Ir的二元催化电极的活性好于镀铂催化电极. 在一定范围内, 随着Ru元素比例增大, 电极活性增强, 而Ir元素含量过大, 电极活性反而稍微降低, 所以Pt-Ir(1∶0.5)/Ti, Pt-Ru(1∶5)/Ti两电极的催化活性相对较好. 本文所制备的三元催化电极的催化活性低于二元催化电极. Pt-Ru/Ti电极催化活性最好, 相同条件下具有最大的电解电流, H₂的电解效率可达95%以上.

Preparation of the Catalytic Electrodes and Study on Their Catalytic Activity for Electro-oxidation of Coal Slurry

Ti based metal or composite catalytic electrodes were prepared by depositing Pt-M catalysts on pure Ti substrate in cyclic voltammetry and were characterized by SEM, XRD, EDS and ICP. The electro-catalytic activity of the electrodes prepared for the electro-oxidation of coal slurry was measured in a two electrode system. Results showed that the electro-catalytic activity of the electrodes was far better than that of the pure Pt electrode. The Ir or Ru addition to Pt/Ti can improve the catalytic activity. With the proportion of Ru increasing to a certain extent, the electro-catalytic activity became better. However, the Ir was otherwise. So the Pt-Ir(1∶0.5)/Ti and Pt-Ru(1∶5)/Ti electrodes had the best catalytic activity. The electro-catalytic activity of the ternary electrodes prepared above was not as good as that of the binary electrodes. The Pt-Ru/Ti electrode had the best electro-catalytic activity and its electrolysis efficiency of hydrogen was up to 95%.