Spin Effect on Oxygen Electrocatalysis

Oxygen involved reactions, including oxygen reduction (ORR) and oxygen evolution reactions (OERs), play a key role in electrochemical energy devices, such as fuel cells and metal-air batteries. Recent theoretical calculations and experimental investigations reveal that the energy loss in ORR/OER is closely related to the triplet O-2 generation/conversion step. However, the spin-related phenomena have long been neglected in understanding of the ORR/OER mechanism. This review highlights recent advances in understanding and application of the spin-related effect in oxygen electrocatalysis. It is demonstrated that the exchange interaction in magnetic catalysts can build a spin-selective channel to filter the electron spins with appropriate orientation in the O-2 generation/conversion step during ORR/OER. It is believed that the introduction of spin effect can establish a more comprehensive understanding of oxygen electrocatalysis and assist designing more reactive oxygen electrocatalysts.