Tailoring an iron-based metal–organic framework for a Zn-ORR/CER battery

Abstract

Chlorine (Cl₂) is a vital industrial product obtained from waste. Replacing the non-sustainable industrial synthesis of Cl₂ with the electrochemical conversion of HCl provides a greener alternative. Moreover, integrating Cl₂ synthesis with Zn-based batteries helps to meet growing energy demands. Herein, we coupled the oxygen reduction reaction (ORR) during discharge and the chlorine evolution reaction (CER) during charge to develop a Zn-ORR/CER battery that utilizes an Fe-based metal organic framework (Fe-Tp) as a robust bifunctional electrocatalyst. This approach facilitates a ‘hitting three targets with one shot’ strategy viz. waste remediation, production of value-added Cl₂, and energy storage and conversion. Apart from providing stable battery performance under corrosive reaction conditions, this report provides an analysis of catalyst renewal during the CER via spectro-electrochemical studies. Moreover, the local pH changes were taken into consideration through detailed microelectrochemical analysis. The assembled battery has fast-charging capability, as demonstrated by powering 35 LEDs for 8 h after 10 minutes of charging, making this a viable battery.