Polymeric carbon nitride materials show intriguing prospects in numerous light-to-energy conversion applications, but seldom studies focus on their triplet energy transfer, leading to the insufficient lifetime for the photochemical process. Inspired by the porphyrin molecular photocatalyst, single-atom sites (Fe-N₄) as triplet sensitizing sites were fabricated in g-C₃N₄ for the preparation of Fe-g-C₃N₄, which processes a long-lived triplet emissive state (τ_PH = 4.93 μs). But under realistic condition for the large-scale production of catalyst, single atoms are inevitable to sinter, resulting in the formation of other metal species. Therefore, the photooxidation of 1,5-dihydroxynaphthalene (1,5-DHN) and the photocatalytic E-Z Isomerization of stilbene were selected as the model reactions to evaluate the influence of various Fe species on the triplet energy transfer. It was found that Fe-N₄ sites promote the triplet energy transfer process, while Fe nanoclusters (Fe⁰) promote the electron transfer and inhibit triplet energy transfer. This finding provides guidance for the rational design of photocatalysts to efficiently improve triplet energy transfer process and its application.

聚合氮化碳材料在众多光能转换应用中显示出有趣的前景，但很少有研究关注它们的三重态能量转移，导致光化学过程的寿命不足。受卟啉分子光催化剂的启发，在 gC ₃ N ₄中制备单原子位点（Fe-N ₄）作为三线态敏化位点，用于制备 Fe-gC ₃ N ₄，其处理长寿命的三线态发射态（τ _PH值 = 4.93 微秒）。但在催化剂大规模生产的现实条件下，不可避免地会出现单个原子的烧结，从而形成其他金属物种。因此，选择 1,5-二羟基萘 (1,5-DHN) 的光氧化和芪的光催化 EZ 异构化作为模型反应，以评估各种 Fe 物种对三重态能量转移的影响。发现Fe-N ₄位点促进三线态能量转移过程，而Fe纳米团簇(Fe ⁰ )促进电子转移并抑制三线态能量转移。这一发现为合理设计光催化剂以有效改善三线态能量转移过程及其应用提供了指导。