Chlorine-Nitrogen Doped Hollow Polyhedral Carbon-Based Catalysts for High Performance Zinc-Air Batteries

It is significant to exploit low-cost and high-activity electrocatalysts for practical zinc-air batteries (ZABs). Herein, a chlorine-nitrogen codoped hollow carbon polyhedron catalyst (Cl-NC-1000) is synthesized by the thermal decomposition of ZIF precursors with a template and intercalating agent of NaCl. Experimental results demonstrate that the synergistic effect of chlorine and nitrogen adjusts the electronic structure of neighboring carbon atoms, facilitating the capturing/releasing of oxygen reduction reaction (ORR) intermediates, thereby reinforcing the intrinsic activity. As a result, the fabricated Cl-NC-1000 catalyst exhibits an outstanding ORR performance, including catalytic activity, selectivity, and stability. When applied in ZABs, the Cl-NC-1000 catalyst maintains a voltage difference of ca. 0.96 V at 5 mA cm-2 and cycles over 300 h with an energy efficiency of 53%, superior to those of commercial Pt/C-based rechargeable ZABs. This work provides an efficient strategy for designing cost-effective and high-activity nonmetallic ORR catalysts.