In Situ Detection of Electrochemical Reaction Surface Area by Optical Weak Measurement

The surface area is key to electrochemical systems, including those in electrocatalysis and energy storage. Studies have shown that the surface area of the electrocatalyst directly affects the electrochemical activity, adsorption performance, and stability of the electrocatalyst. This paper used an optical weak measurement (WM) method, which has little impact on the analyte, to measure the reaction surface area (RSA) that actually participated in the electrochemical reaction. Then compared the RSA obtained by the WM with the total surface area (TSA) obtained by the standard Brunauer-Emmett-Teller (BET) measurement and the active surface area (ASA) obtained by the electrochemical double-layer capacitance (EDLC) method. Their growth trend was consistent, indicating the reliability of the WM method. Compared with the above two methods, the WM method is an in situ detection and easy to operate experimentally, which can help researchers to consider the effect of surface area on electrocatalyst performance more rationally.