CeO2 with diverse morphologies-supported IrOx nanocatalysts for efficient oxygen evolution reaction — Commemorating the 100th anniversary of the birth of Academician Guangxian Xu

IrOx-based catalysts are considered the most promising candidates for oxygen evolution reaction (OER) due to their high efficiency. However, improving their intrinsic catalytic activity is essential for practical application. In this work, CeO2 with three different morphologies (rod, cube, octahedron) and supported IrOx nanoparticles were fabricated, and they display morphology-dependent OER activity. The IrOx/CeO2-rod shows the highest activity; the catalysts have a catalytic activity sequence of rod > cube > octahedron. A plausible mechanism was proposed: the CeO2 support with different morphologies modulates the electronic structure of IrOx by the synergistic interaction promoted by oxygen vacancies between the active component and the support, thereby altering the catalytic activity of the IrOx/CeO2 catalyst.