Metal-organic framework derivative improving cycling reversibility for Zn-Ce redox low battery

Abstract

The zinc-cerium redox flow battery has great potential in the field of energy storage for the merits of high voltage and low cost. However, undesirable dendrites growth and insufficient active sites of Zn anode electrode remain a grand challenge to obtain a good reversibility and cycling stability. Herein, we propose a promising and universal method to stabilize Zn anode by modifying commercial graphite carbon felt with metal–organic framework derivative. Owing to the porous structure and rich active sites of heteroatom N and O introduced by metal–organic framework derivative, the modified carbon felts can effectively induce zinc uniformly nucleation and deposition. As a result, the carbon felt electrode modified with ZIF-8 derivative exhibits a lower overpotential than pristine carbon felt electrode. And it exhibits a high average energy efficient of 80.0 % at the current density of 20 mA cm−2 for 14 cycles, which is better than previous results of Zn-Ce redox flow battery. When modified with cobalt-base ZIF-67 derivative, the energy efficient can even reach up to 86.07 % in first cycle. This work offers a strategy in zinc-based redox flow battery research to improve the reversibility and cycling ability by introducing metal–organic framework derivative.