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A novel method of in-situ catalytic site (CoN x ) construction in macroporous carbon (MPC) is developed. The nitrogen-containing MPC-supported cobalt (Co/N–MPC) catalysts are synthesized via the pyrolysis of a mixture of glucose-urea resin, nano-CaCO 3 , and cobalt nitrate. The nano-CaCO 3 functions as a template to fabricate MPC that provides high electric conductivity and large specific surface area. The catalytic CoN x sites are simultaneously created during the formation of N–MPC. The use of glucose-urea resin as the carbon and nitrogen sources significantly increases the nitrogen content as high as 8.8 at% in the MPC. The synthesized Co/N–MPC demonstrates superb catalytic activity toward oxygen reduction reaction. The direct borohydride fuel cell using the Co/N–MPC shows a power density as high as 170 mW cm −2 which is much higher than the cell using 10 wt.% Pt/C but slightly lower than the cell using 20 wt.% Pt/C as the cathode catalyst at ambient conditions. [ABSTRACT FROM AUTHOR]

In this paper, we report a template-free method to fabricate hollow nitrogen-doped carbon (HNC) by pyrolysis of hollow polyaniline microspheres, which were synthesized by suspension polymerization method. The entire synthesis is simple, environmentally benign, and economic. The oxygen reduction reaction (ORR) activity of the as-prepared HNC catalyst is close to that of the commercial Pt/C catalyst in alkaline media with four electron pathway. Moreover, the HNC shows much better fuel crossover resistance and long-term durability than the commercial Pt/C in alkaline medium. All these features make HNC a potentially promising and suitable substitute for the expensive noble metal catalysts in the next generation alkaline fuel cells. [ABSTRACT FROM AUTHOR]