NiO quantum dot-modified high specific surface carbon aerogel materials as an advanced host for lithium-sulfur batteries

Abstract

Lithium-sulfur batteries (LSBs) have great potential for development in next-generation storage devices, which are severely hampered by the shuttle effect of polysulfides and poor sulfur conductivity. To surmount these problems, a high specific carbon aerogel material (NiOQDs/HCA) modified by NiO quantum dots is constructed in this paper as a sulfur host, NiO quantum dots (NiOQDs) attached to porous carbon substrates provide active sites for the chemisorption and transformation of polysulfides. Meanwhile, HCA makes the entire substrate form a complete conductive network, increasing the speed of electron transport. Based on the above advantages, the LSBs with NiOQDs/HCA as the cathode still has a reversible capacity of 440 mA h g−1 after 900 cycles at 0.5 C and a capacity decay rate of 0.052% after 1000 cycles at 1.0 C. The discharge-specific capacity at 0.1 C also reaches up to 818 mA h g−1 at a high sulfur load of 3.3 mg cm−2, with a capacity retention rate of 66% after 100 cycles.