Synthesis and characterization of IrxRu(1-x)O2 mixed nanocatalysts for the oxygen evolution reaction in PEM water electrolysis by Adam method

Abstract

Developing anodic material has been played an important role in PEMWE technology. In this study, we report characterization of mixed metallic oxides with different composition Ir_xRu_(1−x)O₂ (x = 1, 0.9, 0.8, 0.7, 0.6, 0.5 and 0) synthesized by the Adams method as anodic electrocatalysts for PEMWE. The mechanisms of the thermal decomposition process of precursors to form mixed metallic oxide powders were studied by means of thermal gravity analysis (TGA), X-ray diffraction (XRD) while transmission electron microscopy (TEM) were used to evaluate the crystallographic structure, morphology and size of catalyst particles. The surface reactivity and stability of these oxides was investigated by electrochemical methods including cyclic voltammetry (CV) and anodic polarization in solution of 0.5 M H₂SO₄. Based on the given results, the Ir_xRu_1−xO₂ (x = 0.7) compound was found to be more active than pure IrO₂, more stable than pure RuO₂.. With an Ir_0.7Ru_0.3O₂ anode (the total noble metal loading of 4 mg.cm^-2) and a 20% Pt/C cathode (the total noble metal loading of 1 mg.cm^-2), the potential of water electrolysis was 1.618 V at 1 A.cm^-2.