Critical Role of Functional Groups Containing N, S, and O on Graphene Surface for Stable and Fast Charging Li?S Batteries

Lithium-sulfur (Li-S) batteries are considered one of the most promising energy storage technologies, possibly replacing state-of-the-art lithium-ion (Li-ion) owing to their high density, low cost, and eco-compatibility. However, migration high-order lithium polysulfides (LiPs) surface sluggish electrochemical kinetics pose challenges commercialization. The interactions between cathode LiPs can be enhanced by doping carbon host with heteroatoms, however relatively content (<10%) in bulk carbon, which hardly interact at surface. In this study, grafting versatile functional groups designable properties (e.g., catalytic effects) directly on is proposed enhance LiPs. As model systems, benzene containing N/O S/O atoms vertically grafted uniformly distributed expanded reduced graphene oxide, fostering a stable interface combination experiments density theory calculations demonstrate improvements chemical LiPs, an enhancement kinetics, power, densities.