Ultrathin and Conformal Depletion Layer of Core/Shell Heterojunction Enables Efficient and Stable Acidic Water Oxidation

Ru-based electrocatalysts hold great promise for developing affordable proton exchange membrane (PEM) electrolyzers. However, the harsh acidic oxidative environment of the acidic oxygen evolution reaction (OER) often causes undesirable overoxidation of Ru active sites and subsequent serious activity loss. Here, we present an ultrathin and conformal depletion layer attached to the Schottky heterojunction of core/shell RuCo/RuCoO