Advances in Ta 3 N 5 ‐Based Photoanodes for Photoelectrochemical Hydrogen Production and Beyond

ABSTRACT Photoelectrochemical (PEC) water splitting has garnered significant attention as a highly promising and environmentally sustainable route for direct solar‐to‐hydrogen conversion. Nevertheless, its practical application hinges critically on highly efficient and stable photoanode materials. Tantalum nitride (Ta 3 N 5 ), an n‐type semiconductor featuring an ideal bandgap and suitable energy band edges for water splitting, has emerged as a prominent candidate for PEC hydrogen generation. In this review, recent progress in Ta 3 N 5 ‐based photoanodes for solar energy conversion is comprehensively summarized. It begins with an overview of basic properties of Ta 3 N 5 , with an emphasis on its advantages and key challenges for solar water splitting. Next, the main fabrication methods for Ta 3 N 5 film photoanodes are introduced. Highlighted are the effective performance enhancement strategies via improving light absorption, charge separation, and surface reaction kinetics. Furthermore, the development of Ta 3 N 5 ‐based PEC tandem cells for unassisted overall water splitting is discussed. Beyond hydrogen production, their emerging applications for the coproduction of high‐value‐added chemicals and other hydrocarbon fuels are also presented. Finally, the ongoing challenges and future prospects of Ta 3 N 5 photoanodes for solar fuel production are discussed. It is anticipated that this comprehensive review can provide an instructive guideline for the rational design of high‐performance Ta 3 N 5 ‐based photoanodes toward efficient solar energy conversion and storage.