In-situ deposition of Pd/Pd4S heterostructure on hollow carbon spheres as efficient electrocatalysts for rechargeable Li-O2 batteries

The sluggish kinetics of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) have always restricted the development of lithium oxygen batteries (LOBs). Herein, hollow carbon spheres loaded with Pd/Pd4S heterostructure (Pd/Pd4S@HCS) were successfully prepared via the in situ deposition to improve the electrocatalytic activities for both ORR and OER in LOBs. With the well-dispersed Pd/Pd4S nanoparticles, the hierarchical composite with large specific surface area offers favorable transport channels for ions, electron and oxygen. Especially, the Pd/Pd4S nanoparticles could exhibit excellent electrochemical performance for ORR and OER due to their intrinsic catalytic property and interfacial effect from the heterostructure. Therefore, the LOBs with Pd/Pd4S@HCS as cathode catalyst show improved specific capacities, good rate ability and stable cycling performance. (C) 2021 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.