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

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.