Photocontrolled composites are worth studying because they exhibit different types of heterojunctions and tunable characteristics under different wavelengths of light. Here, photocontrolled heterojunctions constructed from Ho single atom modified Mg_1.2Ti_1.8O₅/g-C₃N₄ exhibit different photocatalytic product selectivities and electron transfer directions under visible and ultraviolet light irradiation, indicating different photocatalytic mechanisms, both of which exhibit excellent photocatalytic performance. The results of XAFS, in situ XPS, and fs-TAS indicated that Ho coordinated with N and O, and preferentially combined with g-C₃N₄ to form more N vacancies, which was beneficial for charge transfer and CO₂ adsorption. The ⁵G₃(³H₆)/³K₇(⁵G₄)/⁵G₅/⁵G₆(⁵F₁) → ⁵I₈ emissions can be absorbed by Mg_1.2Ti_1.8O₅/g-C₃N₄ composites, improving the light capture capability. The synergistic effects of Ho and Mg_1.2Ti_1.8O₅/g-C₃N₄ composites can reduce the ΔG of the key rate-determining step CO₂* → COOH*.

中文翻译：

---

由钬单原​​子修饰的 Mg1.2Ti1.8O5/g-C3N4 构建的光控异质结，具有增强的光催化 CO2 转化能力

光控复合材料值得研究，因为它们在不同波长的光下表现出不同类型的异质结和可调特性。其中，由Ho单原子修饰的Mg _1.2 Ti _1.8 O ₅ /gC ₃ N ₄构建的光控异质结在可见光和紫外光照射下表现出不同的光催化产物选择性和电子转移方向，表明不同的光催化机理，两者均表现出优异的光催化性能。 XAFS、原位XPS和fs-TAS结果表明Ho与N和O配位，优先与gC ₃ N ₄结合形成更多的N空位，有利于电荷转移和CO ₂吸附。 5 G ³ ( ³ H ₆ )/ ³ K ₇ ( ⁵ G ₄ )/ ⁵ G ₅ / ⁵ G ₆ ( ⁵ F ₁ ) → ⁵ I ₈排放可被 Mg _1.2 Ti _1.8 O ₅ /gC ₃ N_吸收4.复合材料，提高光捕获能力。 Ho和Mg _1.2 Ti _1.8 O ₅ /gC ₃ N ₄复合材料的协同作用可以降低关键速率决定步骤CO ₂ * → COOH*的ΔG 。