Executive Summary : | Membrane-based water electrolysis is a promising technique for low-cost production of pure green hydrogen. Proton-exchange membrane (PEM) based electrolysis has several advantages, including non-corrosive dilute basic electrolyte, transition metal (TM) catalyst, and compact cell design. However, efforts towards developing AEM-based water electrolysers are in the initial stage, and few literature reports are available. Bi-functional catalysts are the most suitable alternative, but less efforts have been made for their development. Limited activity, electronic conductivity, and stability are the serious shortcomings of the developed catalysts. Most reports are based on low current density and membrane electrode assembly (MEA) based electrolysers or prototypes are very limited. Therefore, catalyst screening must be done in a prototype electrolyser. Selection of a suitable composition and stable 3D assembled porous hollow microstructures with superior accessible active sites are the most appropriate approach to improve activity and stability. Proper incorporation of rGO in the system not only improves conductivity but also restricts microstructural damage, electrochemical etching, and composition change, improving stability. A generalized spray drying assisted synthetic strategy for bare and rGO incorporated porous hollow spheres has been developed, showing stable bifunctional activity even in MEA. The results provide confidence in developing efficient bifunctional catalysts with activity equivalent or better to benchmark noble metal catalysts. The proposed proposal aims to develop bare and rGO incorporated hollow spheres of TM as superior bifunctional electrocatalysts, showing superior activity even in MEA. |