Improvement of Time-zero Analysis Method in Activity Evaluation of Powder Electrocatalyst for Gas Evolution Reaction (Supporting Information)

In this study, we propose a highly accurate catalyst evaluation method by improving the time-zero analysis, which has been reported as an activity evaluation method for gas evolution powder catalysts. We refined the extrapolation approach to plot in this study’s time-zero analysis as an analytical method. The Tafel slopes obtained with this method for LaNiO3 (LNO) were found to be within the reported range, and the data was consistent in catalytic loading range of 2.5–3.3 mg-LNO cm−2. Using the improved time-zero analysis, the kinetic activity of the gas evolution powder catalyst is possible to be evaluated with high accuracy.