Resource utilization of luffa sponge to produce biochar for effective degradation of organic contaminants through persulfate activation

•A new strategy for the resource utilization of loofah sponge was provided.•The achieved loofah sponge-derived biochar could effectively activate PS.•Pyrolysis temperature largely affects the physicochemical property of LSB.•The carbonyl group was accounted for the generation of reactive radicals.•The excellent electron transfer ability accelerated the degradation of AO7.