Features of design and fabrication of metal oxide-based electrocatalysts

The overall performance of the water splitting electrocatalytic reaction is dominated by HER at the cathode and OER at the anode. These two-half reactions face high activation energy barrier and it requires additional activation energy to drive the reaction. Tremendous efforts with different experimental techniques and synthetic methods have been devoted to fabricating efficient metal oxides-based electrocatalysts. Different synthetic methods performed are critical to the crystallinity, grain sizes, morphologies, structural orientation, and specific surface areas of the prepared metal oxides. Various synthetic methods for the preparation of metal oxide-based electrocatalysts are presented in this chapter. Besides, basic guiding principles of designing metal oxide electrocatalysts for water splitting based on different catalytic activity descriptors, catalytic stability, and surface reconstruction are summarized. The main problems existing in synthetic methods and practical applications of metal oxides are pointed out and possible directions for developing better metal oxides-based electrocatalysts for water splitting are outlined.