Valorisation of argan seeds: Production of cathode material for high-performance lithium-sulphur batteries

Abstract

Porous carbon is considered a key factor in mitigating the shuttle effect, which remains one of the biggest challenges to developing lithium-sulphur (Li-S) batteries. Reusing agricultural waste as a raw material is a sustainable and eco-friendly source for producing carbon. Here we propose fabricating carbonaceous material from argan shells by simple pyrolysis. The synthesis of argan shell carbon (ASC) involved a straightforward approach with non-activating pyrolysis. Carbonisation at three different temperatures was employed to obtain ASC. A high sulphur loading of 70 % was incorporated into the ASC using the melt diffusion method, resulting in the formation of three different sulphur‑carbon composites (ASC@S). All of the prepared materials were characterised and evaluated as cathodes for Li-S batteries. The electrochemical performance of composites was compared, and ASC-800@S was identified as the best-performing composite. Thanks to its excellent properties this material combines (surface area, pore volume, conductivity), it delivers a capacity of 674 mAh g−1 and 513 mAh g−1 after 500 cycles at C/10 and 1C rate, respectively. This work provides a simple, economical, and effective strategy for preparing advanced carbonaceous sulphur host materials and significant improvement of Li-S cell performance.