Pt Nanoparticles Embedded NiFe-LDH Nanoflowers as High-Performance Cathode for Rechargeable Aqueous Zinc-Air Batteries

Abstract

Rechargeable aqueousZn-air batteries (ZABs) are promising due to their high energy density (1370 Wh kg -1 ), safety, and environmental friendliness, but their development is hindered by slow oxygen redox kinetics. Herein, we have synthesized Pt nanoparticles embedded NiFe layered double hydroxide (Pt/NiFe-LDH) nanoflowers via an in situ reduction method. As cathode, Pt/NiFe-LDH can exhibit remarkable bifunctional activity with an impressive ΔE value of 0.631 V, which achieves a half-wave potential of 0.861 V for oxygen reduction reaction and a low overpotential of 262 mV at 10 mA cm -² for oxygen evolution reaction, surpassing commercial Pt/C and RuO 2 benchmarks. When deployed in ZABs, the Pt/NiFe-LDH cathode delivers remarkable cycling stability over 1300 h.