Electrosynthesis of peracetic acid using in-situ generated H2O2 enabled by carbon-based bifunctional electrodes

Abstract

Electrosynthesis of peracetic acid (PAA) using in-situ generated H2O2 is a sustainable route to bypass the complexity and hazards of current industrial production routes of PAA. However, efficient electrochemical operation requires advancements in both electrocatalytic H2O2 production and the subsequent oxidation of acetic acid. Herein, we report a bifunctional carbon electrode for PAA electrosynthesis, which features metal-free carbon catalysts structured on a hierarchical array-like graphene substrate. With such a three-dimensional architecture to maximise active site utilisation and enhance mass transfer, this carbon electrode exhibits acidic H2O2 production performance comparable to metal-based counterparts. Moreover, the same electrode activates OH· from H2O2 by virtue of its surface functional group, facilitating strong oxidation of acetic acid to PAA. In a flow electrolyser that couples H2O2 production and acetic acid oxidation, the bifunctional electrode achieved continuous production of industrially relevant concentrations of PAA at high rates and low energy consumption. Our work highlights the critical role of electrode design for the decentralised synthesis of PAA, providing new insights for the electrification of the chemical industry towards a sustainable future.