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.