Boosting the Performance of Nitrogen-Doped Mesoporous Carbon Oxygen Electrode with Ultrathin 2D Iron/Cobalt Selenides

High-performance and low-cost oxygen electrode catalysts for rechargeable metal–air battery have been regarded as one pivotal issue for the ever-increasing energy-demanding devices like electric vehicles, domestic appliances, and consumer electronics. To develop an effective substitute of noble-metal-based catalysts, the modified nitrogen-doped mesoporous carbon (NMC) is proposed as composite catalysts with a series of 2D transition metal selenides (MSe, M = Fe and/or Co) by liquid exfoliation, anchoring, and thermal activation. By varying the transition metal elements, CoSe@NMC is confirmed as the competitive alternative relative to the coupled commercial catalysts (IrO 2 and Pt/C), with a comparable overpotential for oxygen evolution reaction at 10 mA cm −2 and positively shifted half-wave potential for oxygen reduction reaction even after accelerated durability tests for 5000 cycles. Therefore, this postmodification strategy can promote further design toward the advanced electrode materials for other energy conversion and storage techniques.