Exploring highly durable and active electrocatalysts for water oxidation in acidic electrolytes remains a great challenge, because of the easy dissolution of active sites under harsh working conditions. Maintaining the coordination structure of active sites in the process of acidic oxygen evolution reaction (OER) to resist local active sites dissolution is theoretically viable, but rarely reported. Here, a new type of iridium-based oxide Cr-SrIrO3 with body-centered cubic structure (BCC-Cr-SrIrO3) is designed for boosting acidic-OER. Thanks to this unique atomic structure, an amorphous layer of CrIrOx with edge-shared CrOx and IrOx octahedrons was in situ formed by quick leaching of only Sr over BCC-Cr-SrIrO3 during the OER process. The edge-shared metal-oxygen octahedrons act as a tunable catalytic platform to optimize the acidic-OER, where the electron synergistic coupling effect between bimetallic octahedrons improves the OER activity by tens of times per iridium site with a mass activity of 417.6 A gIr−1 at 0.3 V overpotential; while the strong coordination persistence of iridium sites in the edge-shared octahedrons under working potentials dictates superior durability with a large stability number of 7 × 105 in 0.1 M HClO4. This study promises a new route for the design of superior iridium-based acidic-OER catalysts.
