This manuscript proposed a synthesis strategy for simultaneously constructing defect structure and mixed valence coordinated unsaturated sites (CUS) in Cu-BTC (BTC=1,3,5-trihydroxybenzene) framework. Different defective linkers with increasing pK_a value were used to regulate the defect concentration and Cu¹⁺/Cu²⁺ CUS content. The pK_a value of defective linkers was proved to be inversely proportional to the defect concentration and Cu¹⁺/Cu²⁺ CUS content. Compared with pure Cu-BTC, the defective Cu-BTC samples have obviously improved specific surface area, light absorption, bandgap, and charge carrier separation rate. All of these advantages make defective variants become an excellent bifunctional overall water splitting catalyst with O₂ and H₂ generation rates of 3942 μmol·g^-1·h^-1 and 15107 μmol·g^-1·h^-1, respectively. Although the defective linkers with small pK_a value can create more defects, excessive defects in framework will lead to the parent structure collapse, and can also serve as recombination centers to reduce the photocatalytic activity of materials.

该手稿提出了一种在 Cu-BTC（BTC=1,3,5-三羟基苯）框架中同时构建缺陷结构和混合价配位不饱和位点（CUS）的合成策略。使用具有增加的p K _a值的不同缺陷接头来调节缺陷浓度和Cu ¹⁺ /Cu ²⁺ CUS含量。已证明缺陷接头的 p K _a值与缺陷浓度和 Cu ¹⁺ /Cu ²⁺成反比CUS 内容。与纯Cu-BTC相比，缺陷Cu-BTC样品的比表面积、光吸收、带隙和电荷载流子分离率都有明显提高。所有这些优点使有缺陷的变体成为优异的双功能整体水分解催化剂，O ₂和H _{2 的}生成率分别为3942 μmol·g ^-1 ·h ^-1和15107 μmol·g ^-1 ·h ^-1。虽然p K _a值小的有缺陷的接头会产生更多的缺陷，但框架中的过多缺陷会导致母体结构坍塌，并且还可以作为复合中心降低材料的光催化活性。