Fe,N Co-Doped Mesoporous Carbon Nanosheets for Oxygen Reduction

Carbon nanomaterials codoped with transition metal and nitrogen have appeared as one of the most potential candidates to replace noble metal-based oxygen reduction catalyst. However, it remains a challenge to achieve precise and convenient control over the structural parameters on carbon materials for optimal oxygen reduction reaction (ORR) efficiency. Herein, a straightforward and feasible pore-forming method for fabricating mesoporous carbon nanosheets codoped with transition metal and nitrogen was rationally designed by tactfully introducing zinc nitrate into the carbonization process. When applied for catalyzing ORR, iron and nitrogen codoped mesoporous carbon nanosheets synthesized with the aid of zinc nitrate displayed a half-wave potential of 0.92 V, which was significantly better than the catalyst synthesized without zinc nitrate and commercial Pt/C catalyst. A typical catalyst was methanol tolerable and showed only 8% current decay under alkaline condition after 50 »000 s. The vital roles of zinc nitrate in developing high-performance ORR catalysts were also unraveled.