My research focuses on biochar preparation and application, wastewater nutrient recovery, sustainable agriculture, circular economy in waste management, rural wastewater treatment, and resource reuse. Its core is the molecular-scale structural regulation of biochar-based materials, exploring the structure-activity relationship between surface functional groups (hydroxyl, carboxyl, carbonyl, C-C conjugated bonds), metal-oxygen bonds and material performance via XRD, FTIR and XPS. I study the coupled mechanisms of nitrogen and phosphorus adsorption/recovery, solve nanomaterial recyclability issues, and build a closed-loop system of "wastewater purification-nutrient recovery-agricultural reuse", providing theoretical and technical support for related fields.