Se Atom Doping Enhances the Catalytic Activity of Co@NC for Oxygen Reduction Reaction

As the most promising nonprecious metal oxygen reduction reaction (ORR) catalyst, Co@NC catalysts have attracted much attention. Herein, to further improve the activity of Co@NC catalysts, Co and Se atoms are embedded in metal organic framework-derived nitrogen-doped porous carbon (NC) using a high-temperature reduction strategy, and then Co-Se@NC catalysts are constructed. The ORR catalytic activity of the catalysts is evaluated by rotating disc electrodes, and the results show that the ORR catalytic activity of the Co-Se@NC catalysts is significantly enhanced compared to the Co@NC and Se@NC catalysts, demonstrating that the introduction of Se atoms into Co@NC catalysts can significantly improve the ORR catalytic activity. Spectral characterization and pore size analysis shows that the introduction of Se atoms has multiple effects, including providing new active sites, improving the pore structure of the catalyst, and promoting electron transfer and mass transport. This study shows that the Co-Se@NC catalysts has excellent catalytic performance for ORRs, reaching half-wave potentials of 0.765 V in acidic electrolytes and 0.831 V in alkaline electrolytes, demonstrating that the introduction of Se atoms can effectively improve the ORR catalytic activity, thus providing a unique insight into the rational construction of ORR catalysts.