Recommended electrochemical measurement protocol for oxygen evolution reaction

Abstract

Developing highly active and stable oxygen evolution reaction (OER) catalysts necessitates the establishment of a comprehensive OER catalyst database. However, the absence of a standardized benchmarking protocol has hindered this progress. In this work, we present a systematic protocol for electrochemical measurements to thoroughly evaluate the activity and stability of OER electrocatalysts. We begin with a detailed introduction to constructing the electrochemical system, encompassing experimental setup and the selection criteria for electrodes and electrolytes. Potential contaminants originating from electrolytes, cells, and electrodes are identified and their impacts are discussed. We also examine the effects of external factors, such as temperature, magnetic fields, and natural light, on OER measurements. The protocol outlines operational mechanisms and recommended settings for various electrochemical techniques, including cyclic voltammetry (CV), potentiostatic electrochemical impedance spectroscopy (PEIS), Tafel slope analysis, and pulse voltammetry (PV). We summarize existing evaluation methodologies for assessing intrinsic activities and long-term stabilities of catalysts. Based on these discussions, we propose a comprehensive protocol for evaluating OER electrocatalysts’ performance. Finally, we offer perspectives on advancing OER catalysts from laboratory research to industrial applications.