Measurement Methods on Electrodes and Electrocatalysts for Water Electrolysis (Supporting Information)

Toward decarbonized society with sustainable growth, the use of renewable energy as a primary power source is highly demanded. Water electrolysis is promising to produce hydrogen from renewable energy for energy storage and transportation. In developments of new technologies related to alkaline water electrolysis (AWE) and proton exchange membrane water electrolysis (PEMWE), common measurement techniques are required to compare experimental results fairly among different institutes. In this paper, we introduce common measurement techniques, such as electrochemical half cell and full cell for AWE and PEMWE, evaluation techniques for catalytic activities and durability of catalysts under steady and non-steady operation, advanced synchrotron radiation analysis of catalysts, operando XAFS analysis, and optical observation of gas bubbles in detail, that are recently developed in the project research commissioned by the New Energy and Industrial Technology Development Organization (NEDO).