Synthesis of cobalt-anchored N-doped carbon as an oxygen reduction reaction catalyst for aluminum-air batteries

High-performance, stable and inexpensive catalysts use for oxygen reduction reaction (ORR) process are indispensable in the cathode and play an important role in the practical application and industrialization of metal air batteries. In recent years, highly efficient and stable nonprecious metal catalysts have been the focus of research, and cobalt and cobalt oxides being promising options. Herein, we propose a one-step mixed impregnation method to prepare a nitrogen-doped carbon catalyst, after heat treatment the Co-anchored to N-doped carbon catalyst (Co-N-C) with 10–30 nm of Co uniformly distributed was obtained. Which find that 5% Co loading is enough to obtain excellent ORR catalytic performance. The LSV results show that the half-wave potential of the Co-N-C catalyst is 0.838 V(Vs RHE), which is only 60 mV lower than that of the commercial 20% commercial Pt/C catalyst. Moreover, the Co-N-C catalyst has a smaller Tafel slope, faster reaction kinetics and better durability. After 6000 cycles of cyclic voltammetry testing, the half-wave potential shows a negative shift of only 5 mV. In the aluminum–air battery test, with a catalyst loading of 1 mg·cm−2 in the air electrode, the Co-N-C catalyst shows higher power output and capacity performance under high current compared with the commercial 20% Pt/C catalyst. The Co-N-C catalyst prepared by this simple and scalable method can obtain good output performance in the aluminum–air battery products, which will play a substantial role in the industrialization of aluminum–air batteries.