Recent Advances in Photo-Assisted Electrocatalysts for Energy Conversion

Electrocatalysts are essential for the widespread of promising electrochemical energy conversion/storage technologies, where oxygen reduction/evolution reaction (ORR/OER), hydrogen evolution reaction (HER), and carbon dioxide reduction reaction (CRR) are intensively involved. Much effort has been devoted to regulating the components, phases, crystallinity, facets, morphology, defects to optimize the electronic structures for improved catalytic activity. However, it is still a grand challenge to develop low-cost and efficient electrocatalysts. Strategies beyond the conventional optimization scope are urgently demanded to increase the reaction rate, efficiency, and selectivity of electrochemical energy conversion technologies. Recently, photo-assisted electrocatalysis has attracted extensive research interests due to its appealing benefits for charge transfer, surface electronic structures, and reaction selectivity. It adds a new dimension for electrocatalyst optimization, while it is still in the preliminary stage. A comprehensive and timely review on this specific subject is necessary, aiming to present recent significant achievements and challenges and point out future research directions. In this review, three primary strategies for photo-assisted electrocatalysis are systematically summarized: the photogenerated carriers-assisted, localized surface plasmon resonance (LSPR)-assisted, and photothermal-assisted electrochemical enhancement. In each part, possible mechanisms are outlined and followed by the most recent advances. In the end, key challenges, as well as possible strategies to address them, are highlighted for the hotly developed field.