Waste cotton-derived N-doped carbon as a sustainable metal-free electrocatalyst for oxygen reduction

A superior electrocatalytic metal-free carbon material for oxygen reduction reaction was fabricated using waste cotton as feedstock through a simple sulfuric acidification and subsequent melamine activation at 1000 °C. The carbon possesses hierarchical micro-meso porous feature and a relatively high content of pyridinic & pyrrolic N. The carbon material exhibits a nice electrocatalytic activity with an onset potential of −0.17 V (vs. Ag/AgCl) in alkaline solutions which indicates its great potential in the application of metal/air batteries.