LAUSR

Constructing isotype g‐C3N4/g‐C3N4 heterojunction is an approach to improve the efficiency of g‐C3N4 towards solar‐assisted oxidation of water. Such functional configuration can effectively overcome the intrinsic drawback of rapid charge recombination of g‐C3N4. Here, a modified g‐C3N4, with homogeneous phosphorus doping, is prepared in this work through a phosphide‐involved gas phase reaction. The resulting P‐g‐C3N4 displays altered electronic structure, including upshifted band edge potential, narrowed band gap and improved electronic conductivity. These features allow P‐g‐C3N4 as an outstanding candidate to form isotype junction with pristine g‐C3N4. As expected, the accelerated charge separation and migration in target junction is validated by various measurements. The optimized isotype g‐C3N4/P‐g‐C3N4 heterojunction achieves a photocurrent as high as 0.3 mA cm−2 at 1.23 V vs RHE (AM 1.5G, 100 mW cm−2), representing 8‐fold's enhancement compared with pristine g‐C3N4. The present strategy for constructing g‐C3N4‐based isotype heterojunction networks is found effective for large‐scale manufacturing.