Cathode Framework of Nanostructured Titanium Nitride/Graphene for Advanced Lithium–Sulfur Batteries

Abstract Nanostructured titanium nitride (TiN) and graphene composite electrodes have been fabricated through a facile method, combining ultrasonication with melt‐diffusion of elemental sulfur. Nanostructured TiN particles and tube arrays mechanically mixed with graphene substrate leads to the formation of a porous, stabilized composite structure with enhanced electrical conductivity. Such a framework may facilitate accessibility of electrolyte and fast transfer of charges. The specific capacities of the Li−S batteries with TiN nanotubes/graphene and TiN nanoparticles/graphene composites are 1229 and 1085 mAh g −1 , respectively, after 180 cycles under a 0.1 C rate, which are significantly better than pure TiN nanostructures. The specific capacity and capacity retention were investigated as a function of the TiN nanotube to graphene ratio. The optimal ratio was found to be 1 : 1 TiN/graphene, with the highest capacity retention of 87.5 % after 180 cycles. This 3D hybrid structure may provide a balance of high specific capacity and electrochemical stability, allowing durable and efficient energy storage and conversion over a long cycle life.