An in-situ XAS study of A-site doped ruthenium-based pyrochlores for the oxygen evolution reaction

Developing stable, highly active electrocatalysts for the oxygen evolution reaction is necessary to make water electrolysis economically viable. The current state-of-the-art catalyst, IrO2, is far too expensive and cheaper materials must be utilized. Through a novel synthesis route, we have developed a Y2Ru2O7 pyrochlore which outperforms IrO2 in terms of activity. However, it suffers from stability issues and poor conductivity. Doping the pyrochlore with Pb, Sr or Zn may result in increased Ru-O-Ru orbital overlap, which can both improve the conductivity and the stability of the material. Performing in-situ measurements of the bond lengths as well as the oxidation state during electrochemical operation will reveal how stable the doped electrocatalysts are under actual operation. The most suitable dopant can therefore be chosen to solve the stability issues preventing Y2Ru2O7 from replacing IrO2 as the state-of-the-art OER catalyst.