Distributing sulfidized nanoscale zerovalent iron onto phosphorus-functionalized biochar for enhanced removal of antibiotic florfenicol

•A novel and simple approach is presented to uniformly distribute S-nZVI on biochar.•Phosphorus etching of biochar complexes Fe2+ before its reduction and sulfidation.•Greater reactive surface area of supported S-nZVI increases reactivity with FF.•Sulfur release from the particles was limited during the reaction.