Metal organic frameworks (MOF) are a type of nanoporous materials with large specific surface area, which are especially suitable for gas separation and storage. In this work, we report a new approach of crosslinking UiO-66-(OH)₂ to enhance its hydrogen storage capacity. UiO-66-(OH)₂ was synthesized using hafnium tetrachloride (HfCl₄) and 2, 5-dihydroxyterephthalic acid (DTPA) through a canonical modulated hydrothermal method (MHT), followed by a post-synthesis modification, which is to form a crosslinking structure inside the porous structure of UiO-66-(OH)₂. During the modification process, the phenolic hydroxyl groups on the UiO-66-(OH)₂ reacted with methanal, and HCl aqueous solution and triethylamine served as catalyst (the products denoted as UiO-66-H and UiO-66-T, respectively). Powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), ¹³C nuclear magnetic resonance spectroscopy (¹³C NMR) proved that the crosslinking was formed. The BET specific surface area and the average adsorption pore size of UiO-66-H and UiO-66-T significantly increased after modification. The hydrogen storage capacity of UiO-66-H reached a maximum of 3.37 wt% (16.87 mmol/g) at 77 K, 2 MPa. Hydrogen adsorption enthalpy of UiO-66-T was 0.986 kJ/mol, which was higher than that of UiO-66-(OH)₂ (0.695 kJ/mol). This work shows that UiO-66-(OH)₂ is a promising candidate for potential application in high-performance hydrogen storage.

金属有机骨架（MOF）是一种具有较大比表面积的纳米多孔材料，特别适合于气体分离和存储。在这项工作中，我们报告了一种新的交联UiO-66-（OH）_{2的方法，}以提高其储氢能力。UiO-66-（OH）₂使用四氯化ha（HfCl ₄）和2，5-二羟基对苯二酸（DTPA）通过规范调制水热法（MHT）合成，然后进行合成后修饰，以形成UiO-66-（OH）_2。 UiO-66-（OH）₂的多孔结构内部的交联结构。在改性过程中，UiO-66-（OH）₂上的酚羟基与甲烷甲烷反应，并用HCl水溶液和三乙胺作为催化剂（产物分别表示为UiO-66-H和UiO-66-T）。粉末X射线衍射（PXRD），傅立叶变换红外光谱（FT-IR），¹³ C核磁共振光谱（¹³ C NMR）证明形成了交联。改性后，UiO-66-H和UiO-66-T的BET比表面积和平均吸附孔径显着增加。在77 K，2 MPa下，UiO-66-H的储氢容量最大达到3.37 wt％（16.87 mmol / g）。UiO-66-T的氢吸附焓为0.986 kJ / mol，高于UiO-66-（OH）_2的氢吸附焓（0.695 kJ / mol）。这项工作表明UiO-66-（OH）₂ 是在高性能氢存储中潜在应用的有前途的候选者。