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

The hollow carbon spheres loaded with Pd/Pd4S heterostructure (Pd/Pd4S@HCS) could promote the composition and decomposition of toroid-like discharge product with the efficient bi-functional catalytic activity. [Display omitted] 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.