Structural engineering of cattle manure-derived carbon for lithium–sulfur batteries

Abstract

The large-scale generation and disposal pressure of cattle manure make its high-value conversion an important environmental and resource-utilization issue, and developing low-cost sulfur hosts from this waste is an attractive strategy for lithium–sulfur battery materials. However, the intrinsic relationship among carbonization temperature, framework ordering, pore architecture, surface heteroatoms, and electrochemical response within a single precursor system remains insufficiently understood. Here, a unified pretreatment route comprising water washing, alkali treatment, acid hydrolysis, and oxidative stabilization was combined with carbonization at 650–1050 °C to prepare a series of cattle-manure-derived carbons. The sample obtained at 1000 °C (AH-1000) exhibits a relatively complete three-dimensional conductive framework, a balanced micro/mesoporous texture, and moderate retention of polar N/O sites. As a sulfur host, AH-1000 delivers an initial specific capacity of 690 mAh g⁻¹ at 0.1C, together with better rate response and more stable cycling over 100 cycles than the other temperature-series samples. These results indicate that the electrochemical response of cattle-manure-derived carbons is closely related to the temperature-dependent balance among electrical conductivity, pore structure, and surface-active-site retention. Nevertheless, owing to the intrinsic limitations of the cattle-manure precursor, these carbons still show a lower specific surface area and a less developed pore structure than highly active carbon hosts such as Ketjen Black, resulting in relatively limited sulfur-storage capability. This study therefore provides a structural basis for the further optimization of cattle-manure-derived carbon materials.