Three fundamental questions on one of our best water oxidation catalysts: a critical perspective

Nickel oxyhydroxide (NiOOH) is considered to be one of the best-known catalysts for the water oxidation reaction. Recently, progress has been made in pushing the limits of water splitting efficiency by incorporating NiOOH in photo-electrochemical cell architectures. Despite these cutting-edge advances, some basic questions have yet been fully answered. This perspective highlights the three most critical questions that are considered to be the very first step for any theoretical investigation. We suggest possible ways to answer these questions from a theoretician's perspective. Progress toward this direction is expected to shed light on the origin of NiOOH's success.