Graphitic carbon nitride (g-C₃N₄), as a new type of visible-light-responsive photocatalyst, has a unique 2D building unit, excellent chemical stability, and a tunable electronic structure. At the same time, g-C₃N₄ has a large number of periodically separated N atoms that can act as anchoring sites for various functional materials, particularly single metal atoms (SMAs). Recently, supported single atoms have attracted much attention in the field of photocatalysis. Also, it has been shown that g-C₃N₄ is a wonderful material to support atomically dispersed SMA photocatalysts, such as Pd, Pt, Cu, Co, Ni, and Fe. Herein, the latest progress on g-C₃N₄ synthesis strategies and the synergy between this material and SMA catalysts is summarized. The coordination environment and electronic structure of SMAs on g-C₃N₄ are discussed, and the available characterization techniques for studying the physiochemical properties are summarized. Applications of g-C₃N₄-supported SMA catalysts for photocatalytic hydrogen production, CO₂ reduction, organic synthesis, and nitrogen fixation are reviewed. This review is concluded with a discussion of the remaining challenges and future perspectives. It is hoped that by using SMAs anchored on g-C₃N₄ as examples this review will help to elucidate the fundamentals and the great potential of SMA-based catalysts, and promote their further development.

中文翻译：

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用于高效光催化的单金属原子装饰氮化碳：合成、结构和应用

石墨氮化碳（gC ₃ N ₄）作为一种新型的可见光响应光催化剂，具有独特的二维构建单元、优异的化学稳定性和可调的电子结构。同时，gC ₃ N ₄具有大量周期性分离的N 原子，可以作为各种功能材料，特别是单金属原子（SMA）的锚定位点。近年来，负载型单原子在光催化领域备受关注。此外，已经表明 gC ₃ N ₄是一种很好的材料，可以支持原子分散的 SMA 光催化剂，例如 Pd、Pt、Cu、Co、Ni 和 Fe。在此，gC ₃ N的最新进展总结了_{4 种}合成策略以及该材料与 SMA 催化剂之间的协同作用。讨论了SMA 在 gC ₃ N ₄上的配位环境和电子结构，并总结了可用于研究理化性质的表征技术。综述了 gC ₃ N ₄负载的 SMA 催化剂在光催化制氢、CO ₂还原、有机合成和固氮中的应用。本次审查以对剩余挑战和未来前景的讨论结束。希望通过使用锚定在 gC ₃ N ₄上的 SMA 例如，本综述将有助于阐明基于 SMA 的催化剂的基本原理和巨大潜力，并促进其进一步发展。