Metal-organic frameworks (MOFs)-based composites have been widely applied as photocatalysts because of their synergistic effect between the two individual component. Herein, TiO₂@NH₂-MIL-125(Ti) nanocomposites which possess unsaturated titanium—oxo clusters, mesoporous structure, and intimate interface were successfully constructed via an in-situ distilled water-etched route. The X-ray photoelectron spectroscopy (XPS) measurements indicated strong electronic interaction between TiO₂ and NH₂-MIL-125(Ti), confirming the formation of TiO₂@NH₂-MIL-125(Ti) nanocomposite. Photoelectrochemical and thermodynamics measurements showed that TiO₂@NH₂-MIL-125(Ti) nanocomposites have improved charge separation efficient and decreased transfer resistance of the carriers within the heterojunction interfaces, which facilitates the photoexcited electrons transfer and reduction of the Cr(VI) species. Therefore, the optimal TiO₂@NH₂-MIL-125(Ti) nanocomposite demonstrated superior performance compared to NH₂-MIL-125(Ti) and NH₂-MIL-125(Ti) derived TiO₂. Based on the free radical trapping experiment and electron paramagnetic resonance (EPR) measurements, a possible type-II scheme was proposed for the enhanced photocatalytic activity over the TiO₂@NH₂-MIL-125(Ti) nanocomposite.

基于金属有机框架（MOF）的复合材料由于它们在两种单独组分之间的协同作用而被广泛用作光催化剂。在此，通过原位蒸馏水蚀刻路线成功构建了具有不饱和钛-氧簇、介孔结构和紧密界面的TiO ₂ @NH _{2 -MIL-125(Ti)纳米复合材料。}X 射线光电子能谱 (XPS) 测量表明 TiO ₂和 NH ₂ -MIL-125(Ti) 之间存在强烈的电子相互作用，证实了 TiO ₂ @NH ₂ -MIL-125(Ti) 纳米复合材料的形成。光电化学和热力学测量表明，TiO ₂@NH ₂ -MIL-125(Ti)纳米复合材料提高了电荷分离效率并降低了异质结界面内载流子的转移电阻，从而促进了光激发电子转移和Cr(VI)物种的还原。因此，与NH ₂ -MIL-125(Ti)和NH ₂ -MIL-125(Ti)衍生的TiO _{2相比，最佳的TiO 2} @NH ₂ -MIL-125(Ti)纳米复合材料表现出优异的性能。基于自由基捕获实验和电子顺磁共振 (EPR) 测量，提出了一种可能的 II 型方案，用于增强 TiO ₂ @NH ₂ -MIL-125(Ti) 纳米复合材料的光催化活性。