Contribution of sodium alginate-derived bio-carbon towards enhanced electrochemical performance of CuS anodes in Na Batteries

Abstract

Copper sulfide (CuS), under the category of metal sulfide, remains as promising anode for Sodium-ion Batteries (SIBs) with a theoretical capacity of 560 mAhg⁻¹. CuS suffers from polysulfide formation, severe capacity fading upon cycling. To address these issues addition of bio-carbon is sought as a measure in this work. A porous carbon has been successively synthesized from sodium alginate source with a specific surface area of 38.78 m²g⁻¹ and an average pore volume of 3.40 nm. The addition of prepared porous carbon to copper sulfide (CuS) enhances stability in the electrochemical performance with the value of 442 mAhg⁻¹ being the initial discharge capacity observed at a current density of 100 mAg⁻¹ over 500 cycles. The technology in performing solid-state reaction is well established and does not demand high infrastructure for atmospheric control thus facilitating large-scale production. Therefore, this work throws light on the benefit of adding bio-carbon to CuS.