HsGDY on Ni Foam for Loading MoS2/Ni3S2 to Enhance the Performance on Lithium–Sulfur Batteries

Abstract

Lithium–sulfur batteries are considered important devices for the power of movable equipment, but there are still some challenges that limit their applications, such as how to obtain a cathode for high sulfide adsorption and rapid conversion. Here, a new strategy is proposed to enhance the performance of lithium–sulfur batteries by growing 3-dimensional hydrogen-substituted graphdiyne (HsGDY) layers on Ni foam via Glaser cross-coupling reaction to anchor MoS2/Ni3S2, enhancing the conductivity of host material of S. The results show that the 3-dimensional HsGDY framework enables the fast adsorption of lithium polysulfides and the Ni3S2/MoS2 performs as the reaction center with a low charge transfer resistance. The charge capacity of Ni@HsGDY/MoS2/Ni3S2 cell is up to 1,234.7 mAh·g−1 at the first circle, and the specific capacity keeps 486 mAh·g−1 after 500 cycles at a current density of 2 C. The incorporation of HsGDY into the cathode promotes the adsorption and the conversion of polysulfides, paving a path to obtain lithium–sulfur batteries with high energy density.