Acid-Stable Oxides for Oxygen Electrocatalysis

Assessing materials' stability under operating conditions is of critical importance to the development of device-oriented electrocatalysts, whereas few efforts have been devoted to this on a large scale.In this work, using the Materials Project data, we explore the aqueous stability of 47,814 non-binary metal oxides under typical oxygen reduction/evolution reaction conditions and identify 68 likely acid-stable candidates for oxygen electrocatalysts.We also construct an "acid-stable periodic table" to guide the search of new acid-stable materials for electrocatalysis.Electrocatalysis is fundamental to renewable energy applications by facilitating energy conversion between electricity and chemicals. 1The electrochemical process involving oxygen, such as the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER), however, have become bottlenecks for applications in fuel cells and electrolyzers due to the relatively poor performance of even the best known ORR/OER electrocatalysts.Acid-based devices are more promising in practical applications because of the commercially accessible proton exchange membranes and high current density, 2,3 but the highly oxidizing and acidic environment severely limits the stability of most materials as catalysts.