Tailor-made graphene aerogels with inbuilt baffle plates by charge-induced template-directed assembly for high-performance Li–S batteries

Abstract

Graphene as a host material has attracted intense interest to accommodate the sulfur for lithium–sulfur (Li–S) batteries. Nevertheless, there is still a major challenge on how to modulate the nanostructure of graphene architectures to further enhance the electrochemical performance. Herein, self-closure graphene aerogels with inbuilt baffle plates (SGA) were prepared by a combined strategy involving electrostatic assembly, hydrothermal fixing, polydopamine (PDA) coating, and annealing. The electrostatic assembly between graphene oxide (GO) and polystyrene sphere@polydopamine (PS@PDA) is the key factor to form the self-closure aerogels and the graphene sheets wrapped onto the PS@PDAs are responsible for the formation of the baffle plates. When employed as the host material for Li–S batteries, the as-made SGA can contribute to promotion of the transport of electrons, increasing the sulfur loading, confining the dissolution and diffusion of lithium polysulfides, and accommodating the volume expansion. As a result, the as-made SGA–sulfur composite can deliver an outstanding cycling stability of 509 mA h g⁻¹ after 400 cycles at 1C. The present work will provide a simple and effective approach to tuning the assembly of graphene and further configuring the tailor-made host materials for high-performance Li–S batteries.