Surface morphology and electrochemical properties of RuO2-doped Ti/IrO2-ZrO2 anodes for oxygen evolution reaction

摘要

RuO2-doped IrO2-ZrO2 ternary oxide coatings with different Ru/Ir/Zr mole ratios were synthesized using a sol-gel route. The surface morphology was determined by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and energy dispersive spectroscopy (EDS) analysis. The electrochemical behavior was investigated using linear sweep voltammetry (LSV), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and accelerated life test (ALT). The results showed that the compositions of the coatings are rutile IrO2 and RuO2. ZrO2 is present as an amorphous phase in the coatings. The coating with Ru content of 21 mol% shows a compact structure with needle-like crystals dispersed. With the increase in Ru content, the porous and cracked structure of the ternary oxide coating of increased active surface area is obtained. Increasing Ru content improves the electrocatalytic activity, but worsens the stability of the coating in OER. The coating with Ru content of 21 mol% shows good electrocatalytic activity and the longest service lifetime in OER. (C) 2018 Elsevier B.V. All rights reserved.