NiFe LDH-CoPc/CNTs as novel bifunctional electrocatalyst complex for zinc-air battery

A new type of composite electrocatalyst was designed and prepared with NiFe layered double hydroxides (LDHs) for oxygen evolution reaction (OER) and CoPc for oxygen reduction reaction (ORR) supported on carbon nanotubes (CNTs). The NiFe LDH-CoPc/CNT composite exhibits higher electrocatalytic activity and stability than the commercial precious metal catalyst Pd/C + Ru/C in 6 M KOH electrolyte. The resulting rechargeable Zn-air battery showed high discharge voltage at 195 mW cm(-2). The discharge voltage is around 1.08 similar to 0.95 V and the charge voltage is lower, 2.07 V, after the cycle of 300 h at 80 mA cm(-2), indicating that zinc-air battery possessed high reversibility and durability over long charge and discharge cycles.