AlN nanoparticles anchored on cross-linked N-doped carbon nanosheets as sulfur hosts for lithium-sulfur battery

Abstract

Lithium–sulfur (Li–S) battery has attracted extensive attention owing to its high theoretical energy density, low cost, and environmental friendliness. On the other hand, there are also some scientific problems, such as volume expansion and the shuttle effect of polysulfides. Here, three-dimensional cross-linked N-doped carbon nanosheets (NCNs) loaded with aluminum nitride (AlN) nanoparticles were synthesized and used as sulfur hosts for Li–S battery. The AlN@NCNs nanocomposites greatly improved the cycling and rate performance of Li–S battery. The AlN@NCNs/S nanocomposites provided a stable discharge capacity of 507.4 mAh/g after 400 cycles at 0.5 A/g, with a Coulombic efficiency of up to 99 %. After 500 cycles at 1.0 A/g, the capacity kept at 435.2 mAh/g. The polar AlN nanoparticles have strong adsorption on polysulfides, which obviously relieve the shuttle effect of polysulfides. Therefore, combining nitrogen-doped carbon nanosheets with metal nitride nanoparticles enhanced the electrochemical performance of Li–S batteries.