Tantalum nitride photoanodes: a promising future for photoelectrochemical water splitting?

Photoelectrochemical (PEC) water splitting is a promising method for sustainable hydrogen production. Among potential materials, tantalum nitride (Ta 3 N 5 ) has emerged as a leading candidate due to its favorable band gap and high theoretical efficiency. This review highlights recent advancements in the synthesis, doping, and surface modification of Ta 3 N 5 photoanodes, which have enabled photocurrent densities approaching the material’s theoretical limit of 12.9 mA/cm² at 1.23 V vs. RHE. Despite these advancements, significant challenges remain, particularly in achieving long-term stability. We critically evaluate the feasibility of meeting the U.S. Department of Energy’s targets and provide insights into more achievable and realistic goals for PEC systems based on Ta 3 N 5 , focusing on efficiency, lifetime, and cost competitiveness.