Inverse doping IrOx/Ti with weakened Ir-O interaction toward stable and efficient acidic oxygen evolution

The acidic oxygen evolution reaction (OER) faces great difficulty in concurrently addressing the site-specific activity and stability of the up-to-date choice Ir-based catalysts. Herein, we adopted a new inverse doping strategy to devise a Ti atomic doping into the surficial IrOx/Ir matrix to investigate the boosting effect of Ir-O-Ti motifs toward OER. Notably, only 1.92 wt % Ti introduction leads to 3.6 times and an order of magnitude improvement in intrinsic activity and stability, respectively, ascribed to the creation of abundant Ir-O-Ti motifs. While the Ti sites donate electrons to weaken the Ir-O interaction and thereby ignite Ir sites activity via adsorbate evolution mechanism (AEM), the restricted O-O bond formation in the lattice oxygen mechanism (LOM) and the widened stable region of Ir species help enhance the stability. This work provides a novel insight into the reactivity of atomic-level interface motifs in heterogeneous components, which inspires further design of advanced catalysts.