Template-directed synthesis of nitrogen-and sulfur-codoped carbon nanowire aerogels with enhanced electrocatalytic performance for oxygen reduction

摘要

Heteroatom doping,precise composition control,and rational morphology design are efficient strategies for producing novel nanocatalysts for the oxygen reduction reaction (ORR) in fuel cells.Herein,a cost-effective approach to synthesize nitrogen-and sulfur-codoped carbon nanowire aerogels using a hard templating method is proposed.The aerogels prepared using a combination of hydrothermal treatment and carbonization exhibit good catalytic activity for the ORR in alkaline solution.At the optimal annealing temperature and mass ratio between the nitrogen and sulfur precursors,the resultant aerogels show comparable electrocatalytic activity to that of a commercial Pt/C catalyst for the ORR.Importantly,the optimized catalyst shows much better long-term stability and satisfactory tolerance for the methanol crossover effect.These codoped aerogels are expected to have potential applications in fuel cells.