Cesium Lead Bromide Perovskite-Based Lithium-Oxygen Batteries.

The main challenge for lithium-oxygen (Li-O) batteries is their sluggish oxygen evolution reaction (OER) kinetics and high charge overpotentials caused by the poorly conductive discharge products of lithium peroxide (LiO). In this contribution, the cesium lead bromide perovskite (CsPbBr) nanocrystals were first employed as a high-performance cathode for Li-O batteries. The battery with a CsPbBr cathode can exhibit the lowest charge overpotential of 0.5 V and the best cycling performance of 400 cycles among all the reported perovskite-based Li-O cells, which represents a new benchmark. Most importantly, the density functional theory (DFT) calculations further prove that the rate limitation step during OER processes is the decomposition of LiO to form O and Li, and the weak adsorption strength between CsPbBr surfaces and LiO results in a low charge overpotential for the CsPbBr-based Li-O battery. This work first demonstrates the good potential of CsPbBr for application in metal-air batteries.