In-situ assembly of TiO2 with high exposure of (001) facets on three-dimensional porous graphene aerogel for lithium-sulfur battery

Resulting from the development of electric vehicles, high energy-density Li-S batteries have recently attracted ever-increasing attentions worldwide. However, continuous dissolution of cathodic sulfur and followed shuttle effect of polysulfides lead to very limited service lifetime for currently-applied Li-S batteries. Herein, a 3D porous graphene aerogel (GA) decorated with high exposure of anatase TiO2 (001) nanoplatelets is proposed as robust host to immobilize cathodic sulfur. Compared with commonly used TiO2 (101) nanoparticles, the TiO2 (001) nanoplatelets have highly matched lattices with graphene (002) nanosheets, thus facilitating the electronic transfer. The in-site assembled TiO2@GA host exhibits superior sulfur-immobilized capability, which cannot only entrap sulfur by physical confinement, but also capture dissoluble sulfurous species by chemical bonding. The fabricated S@TiO2@GA cathode shows excellent electrochemical performance with high discharge capacity, superior rate capability, and durable cycling stability as well, supposed to be a promising cathode for high-performance Li-S battery applications. (C) 2020 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.