混合配体合成金属有机骨架UiO-66吸附剂的研究

Synthesis of metal organic framework UiO-66 adsorbent by mixed ligands

金属有机骨架UiO-66具有良好的化学和热稳定性。为提高其氢气吸附能力,探究其在氢气储存领域中的应用,采用溶剂热法合成高纯度UiO-66,并以不同摩尔比的对苯二甲酸和2-氨基对苯二甲酸合成NH2-UiO-66材料,分别对UiO-66和混合配体合成的NH2-UiO-66进行X射线衍射、热重分析、N2物理吸附、扫描电镜和氢气吸附性能等分析和表征,结果表明,NH2-UiO-66的结晶度随着2-氨基对苯二甲酸的加入先逐渐变强,后又渐渐变弱。氢气吸附性能也随着2-氨基对苯二甲酸的加入呈现相同的特点,其中,对苯二甲酸与2-氨基对苯二甲酸的摩尔比为3∶2时,所合成的NH2-UiO-66的氢气吸附性能最佳,比单配体合成的UiO-66提高33%,具有良好的应用前景。

Metal organic framework UiO-66 has high chemical and thermal stabilities.In order to improve its adsorption capacity to hydrogen and explore its application in the field of hydrogen storage sector,a highly pure UiO-66 is synthesized by solvothermal method,and NH2-UiO-66 materials are synthesized through using pure UiO-66 to react with different ratios of 2-aminioterephthalic acid and terephthalic acid.The synthesized UiO-66 and NH2-UiO-66 are all characterized by X-ray diffraction,thermogravimetric analysis,nitrogen adsorption,scanning electron microscopy and hydrogen adsorption.It is found that with the addition of 2-amino terephthalic acid,NH2-UiO-66 absorbents’crystallinity and adsorption to hydrogen both strengthen gradually and weaken then.When the ratio between terephthalic acid and 2-aminoterephthalic is 3∶2,the synthesized NH2-UiO-66 absorbent has the best adsorption performance to hydrogen,which is 33%higher than that of UiO-66 synthesized by a single ligand.