Our industrial demands are ever-changing in response to a dynamic, burgeoning market, and with those demands comes the need to develop new strategies to both improve the quality of water and extend its usefulness in our industrial processes. In this regard, electrocatalysis has emerged into the limelight of academic interest as a versatile method for industrial wastewater treatment. Despite substantial improvements in catalyst design, few studies center on their long-term performance, and even fewer delve into catalyst stability against complex, real wastewater matrices. Therefore, we report a protocol for systematically evaluating an electrocatalyst under such conditions, with an emphasis on 1) rapid identification of constituents that are detrimental to catalyst activity and selectivity, and 2) assessment of catalyst lifetime while minimizing the number and duration of experiments. Synthesized catalysts are first exposed to various model wastewater electrolytes referenced from EPA Discharge Monitoring Reports (DMRs) and tested for short-term stability via conventional hydrodynamic voltammetry (RRDE). They are then assessed under a flow cell setup at higher current densities and contaminant concentrations to mimic a more practical environment or emulate accelerated stress conditions. To showcase our methodology, we select the 2-electron oxygen reduction reaction (2e- ORR) for H2O2 synthesis as a model reaction, in which we monitor the changes in overpotentials and H2O2 faradaic efficiency at each current density over time. The findings of this study will elucidate key deactivation phenomena that inhibit performance and provide insight into the development of more robust electrocatalysts.

Towards practical electrocatalysis for industrial wastewater treatment: The stability of H2O2 electrosynthesis

ACS Fall 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.