Solar hydrogen generation using niobium-based photocatalysts: design strategies, progress, and challenges

Abstract

Solar water splitting using semiconductor photocatalysts is being extensively studied worldwide. During the past few decades, to meet the feasibility and economic viability criteria of practical applications, a large library of photocatalyst materials has been developed. Niobium (Nb)-based semiconductors comprise a large family of promising photocatalyst materials and have attracted burgeoning attention on account of their unique physicochemical and structural properties. This work intends to provide a comprehensive summary of the progress that has been made in solar water splitting using niobium based photocatalysts and elucidate why they offer competitiveness regarding the photocatalytic water splitting activity. For convenience, niobium-based semiconductor photocatalysts are categorized into seven groups with respect to their crystal structures and chemical formulae, including niobium pent oxide (Nb2O5), A(4)O(17), ANb(3)O(8), ANb(2)O(6), ANbO(4), A(3)NbO(7 )niobates, and perovskites. Emphasis is given to the critical aspects of the structure-activity relationship, the most significant results contributing to the progress, and the current strategic trends to attain enhanced performance. Finally, tantalizing scientific challenges and the most promising avenues towards efficient water splitting based on niobium-based photocatalysts are identified and discussed. (C)& nbsp;2021 Elsevier Ltd. All rights reserved.