Influence of preparation process on electrocatalytic activity of Ti/IrO2 + MnO2 anodes for oxygen evolution in 0.5M Na2SO4 solution

摘要

The Ti/IrO2(x) + MnO2(1-x) anodes have been prepared by thermal decomposition of an H2IrCl6 and Mn(NO3)(2) hydrosolvent. A four-factor and three-level orthogonal experiment is designed to optimise the preparation process of Ti/IrO2 + MnO2 anodes for oxygen evolution in 0.5M Na2SO4 solution. Surface characteristics and electrocatalytic activity of Ti/IrO2 + MnO2 anodes are investigated by a field emission scanning electron microscope and cyclic voltammetry. The orthogonal analysis indicates the order from the main to minor factor is thermal decomposition temperature, matrix etching time, Ir4+/Mn2+ mole ratio and total metal concentration of the precursor. Further optimisation experiments are also performed for the two main factors (thermal decomposition temperature and matrix etching time) based on the orthogonal experimental result. As a result, an optimal technological combination of 400 degrees C x 45 min x 6 : 4 x 0.3 mol L-1 is obtained. Moreover, a brief morphological verification is carried out.