Synergistic integration of N-doped carbon network foam and Ni nanoparticles in wood-derived frameworks for high-performance lithium–sulfur batteries

Abstract

The practical application of lithium sulfur (Li-S) batteries is severely hindered by the shuttle effect and sluggish redox kinetics. Herein, a multifunctional cathode matrix is developed by incorporating Ni nanoparticles and N-doped carbon network foam (NCNF) into a wood-derived carbon framework. The intrinsic anisotropic microchannels offer sufficient space for sulfur loading and fast pathways for ion transport. Notably, Ni nanoparticles promote the carbonization and structural reconstruction of NCNF, which effectively improves the overall electrical conductivity. Combined with rapid ion transport, the redox kinetics are substantially enhanced. In addition, NCNF provides abundant polar sites for the chemical anchoring of lithium polysulfides. Benefiting from the catalytic effect of Ni nanoparticles, the shuttle effect is also effectively suppressed. Consequently, the CBW/NCNF@Ni/S cathode exhibits a high initial discharge capacity of 1278.5 mAh g −1 and a reversible capacity of 686.3 mAh g −1 after 480 cycles at 0.5C. Even under a high sulfur loading of 7.96 mg cm −2 , a capacity of 656.5 mAh g −1 is retained. This work demonstrates a synergistic strategy combining structural engineering and catalytic modification to fabricate high-performance sulfur hosts, providing a feasible pathway toward practical Li-S batteries with high energy density and long-term cycling stability.