Preparation and performance study of high-performance lignin carbon-based sulfur host materials

The development of lithium-sulfur batteries, which are a new type of energy storage device, is hindered by the poor performance of sulfur cathodes and the shuttle effect of polysulfides.In this study, a composite precursor was successfully constructed through the hydrophobic self-assembly of lignin, carbon nanotubes (CNTs), and zinc carbonate, wherein lignin molecules encapsulate CNTs. Subsequently, high-temperature gas-phase exfoliation and in-situ activation of the precursor yielded a three-dimensionally interconnected lignin carbon/CNTs composite material (LPC/CNTs), as sulfur host to enhance the electrochemical performance. The results indicate that LPC/CNTs as a sulfur-hosting material, under calcination at 700 °C with a 10 % CNTs addition, the initial discharge specific capacity reaches 1138 mAh g⁻¹ at 0.1 C and maintains a discharge specific capacity of 504.09 mAh g⁻¹ after 300 cycles at 1 C. These findings suggest that the LPC/CNTs composite material, featuring abundant pore structures and three-dimensionally interconnected conductive networks, is a promising sulfur-hosting material for lithium-sulfur batteries. This study not only offers a novel approach for the high-value utilization of industrial lignin but also provides fundamental data for the development of new energy materials.