Hydrogen peroxide is an oxidizing agent with a variety of applications in both industrial and household settings. Researchers are working on developing better and better ways to produce H₂O₂, such as photocatalytic H₂O₂ evolution techniques, which are more sustainable and environmentally friendly. The reaction simply uses energy from the sun, water and oxygen to make H₂O₂. Another key player - the focus of a recent review by researchers at Tohoku University - is a catalyst to speed up this reaction called graphitic carbon nitride (g-C₃N₄). The research team took a deep dive into g-C₃N₄ to highlight not just what this catalyst does during the photocatalytic H₂O₂ evolution reaction, but how it is made in the first place.

This review study is one of the first that focuses on the "nanoarchitectonics" of g-C₃N₄, which is when you construct a material by organizing building blocks at the nanoscale level - like deciding the position of every single brick in your dream home's architecture. This level of precision is the key to achieving physical and chemical properties that could allow this catalyst's production to be scaled-up from being confined to laboratory research to big industrial and commercial applications.

"Recent reviews have discussed fabrication methods, challenges, and perspectives for g-C₃N₄ materials used in H₂O₂ generation, but a comprehensive review specifically addressing the recent advancements in nanoarchitectonics of layered g-C₃N₄ for photocatalytic H₂O₂ generation was still needed," says Xiao Zhang (Advanced Institute for Materials Research (WPI-AIMR), Tohoku University).

Using heterostructure design, g-C₃N₄ has the potential to produce H₂O₂ cleanly and efficiently. Additionally, the review covers other potential strategies to make the most out of g-C₃N₄ such as defect engineering strategies, the effect of metal doping, semiconductor heterostructure construction, and more. This research underlines important bottlenecks that need to be overcome in order to make largescale industrial production a reality.

The findings were published in Coordination Chemistry Reviews on March 28, 2026.