Sustainable Cow Hair Biocarbon‐Sulfur Cathodes with Enhanced Electrochemical Performance

Abstract

A sustainable cow hair‐based biocarbon/sulfur composite was prepared via a melt‐diffusion process and used as cathode for lithium–sulfur (Li−S) batteries, exhibiting high capacity, good rate capability, and excellent cyclability. The effect of the activation process during the formation of the biocarbon was deeply analyzed by thermogravimetry, N2 adsorption, X‐ray photoelectron spectroscopy, scanning and transmission electron microcopy, among others. A correlation between the composition and the surface area with the electrochemical performance was found. The best results were obtained using an activated sample and composite electrode containing 73 wt % sulfur, which present an initial discharge capacity of around 1200 mAh/g and 799 mAh/g after 100 cycles at a current density of 0.1 A/g. Moreover, a specific capacity of ~701 mAh/g was measured at 1 C. The great electrochemical performance of this electrode in Li−S batteries is attributed to the porous carbon structure. Taking into account that hair is one of the major waste produced in the leather sector, this work presents a promising approach to reuse this material by giving it added value through the preparation of carbon/sulfur composites for high‐performance Li−S batteries.