Strategy for boosting Co-Nx content for oxygen reduction reaction in aqueous metal-air batteries

Electrocatalyst is the pivotal component promoting the kinetics of oxygen reduction reaction in aqueous metal-air batteries . However, the content of increased bond as the active species is usually limited by the metal loading, tiny pore canal, insufficient nitrogen further restraining the electrocatalytic effectiveness of single-atom catalysts in oxygen reduction reaction (ORR). Herein, Co, N-dual doped carbon (Co/NNC) is prepared by a versatile strategy of the combination approach of SiO 2 template with extra nitrogen source. Based on ZIF-67 prepared with the assistance of SiO 2 template, the extra nitrogen source was introduced in the high-temperature pyrolysis procedure. The material characterizations of XRD , SEM, HRTEM , BET, Raman and XPS are conducted to synthetically analyze the functional role of extra nitrogen source. Moreover, the Co/NNC with increased Co-N x active sites is employed into two aqueous metal-air batteries of Zn-air and Mg-air batteries, which exhibits excellent performances especially in the aspects of discharge specific capacity, discharge stability and power density.