Preparation and properties of transition metal nitrides caged in N-doped hollow porous carbon sphere for oxygen reduction reaction
(1. Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221116, China;
2. State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China)
2. State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China)
Abstract: A series of transition metal nitrides (MxNy, M=Fe, Co, Ni) nanoparticle (NP) composites caged in N-doped hollow porous carbon sphere (NHPCS) were prepared by impregnation and heat treatment methods. These composites combine the high catalytic activity of nitrides and the high-efficiency mass transfer characteristics of NHPCS. The oxygen reduction reaction results indicate that Fe2N/NHPCS has the synergistic catalytic performance of higher onset potential (0.96 V), higher electron transfer number (~4) and higher limited current density (1.4 times as high as that of commercial Pt/C). In addition, this material is implemented as the air catalyst for zinc-air battery that exhibits considerable specific capacity (795.1 mA·h/g) comparable to that of Pt/C, higher durability and maximum power density (173.1 mW/cm2).
Key words: N-doped porous carbon; transition metal nitrides; Zn-air battery; oxygen reduction reaction; fuel cell