具有富氮孔表面的多孔晶态材料的合成及其在温和条件下气体吸附性能的研究

The energy shortage and environmental deterioration seriously threaten the sustainable development of the whole mankind. Now, it is an important research project to find new porous materials for storage hydrogen and capture carbon dioxide. Porous coordination polymers (PCPs), endowing with large surface areas, tunable pore diameters, and functionalized pore surfaces, have currently attracted much attention. Recent research reveals that PCPs with N-atom-modified pore surfaces can strongly bind with gas molecules, and thus show promising prospect for gas storage at room temperature. Encouraged by these good results, in this project, we propose to use pentaerythritol or its derivatives as templates, metal ions and poly-nitrogen heterocyclic ligands as building units to construct three-dimensional PCPs containing N-rich pore surfaces. After carefully characterizing their structures by infrared spectra (IR), thermogravimetric analysis (TGA), elemental analysis (EA), and X-ray single-crystal/powder diffraction, we will exchange the template molecules with low boiling point solvent and thus get porous framework materials not only containing N-rich pore surfaces but also possessing large surface areas. Emphasis will be made on investigating their abilities to upload hydrogen and capture carbon dioxide in mild conditions, and analyzing the influence of the degree of N-rich in surfaces to the uploaded amount of gas molecules, as well as summarizing the design and synthesis rules of N-rich PCPs materials with good gas storage properties.In addition, to further reveal the interaction mechanism between the N-rich pore surfaces and gas molecules, and give reasonable explanation for the gas sorption results, a strategy of theoretical calculation will be used to simulate their adsorption behaviors to H2/CO2 molecules. A theoretical model for PCPs materials with good gas storage capacity will be established, and the theoretical system of PCPs materials in gas storage field will be improved. These result will pave a new way for designing and developing new PCPs materials for gas storage in future. Also, it will provide theoretical and practical basis for realizing H2 storage and CO2 capture at room temperature, and raising the applications of PCPs materials in energy and environmental fields.

孔表面由N原子修饰的多孔配位聚合物（PCPs）材料对气体分子能产生较强的作用，并表现出良好的气体吸附性能。本项目拟以季戊四醇等多羟基化合物为模板，将多氮杂环配体与金属离子组装得到孔表面全部或接近于全部由N原子组成（本项目书中定义为富氮孔表面）的PCPs材料，利用溶剂交换作用去除模板分子，得到同时具有富氮孔表面和大比表面积的新型多孔晶态材料；重点研究它们在温和条件下存储氢气和俘获二氧化碳的能力，探讨孔表面富氮程度对气体分子作用以及气体存储量的影响，并总结具有良好气体存储性能的富氮多孔晶态材料的设计与合成规律；进一步利用理论计算的方法模拟富氮PCPs对气体分子的吸附行为，揭示富氮孔表面对气体分子的作用机制，建立具有良好气体存储性能的PCPs材料的理论模型，完善PCPs材料在气体存储领域的理论体系，为实现室温存储氢气和俘获二氧化碳，提高PCPs材料在能源和环境领域的应用提供理论和实验依据。

在项目21363001的资助下，四年来，主要开展了以季戊四醇等多羟基化合物为模板，组装基于多氮杂环配体的PCPs材料，研究了它们存储氢气和俘获二氧化碳的能力，探讨孔表面富氮程度对气体分子作用以及气体存储量的影响，并总结具有良好气体存储性能的富氮多孔晶态材料的设计与合成规律；揭示了富氮孔表面对气体分子的作用机制，完善PCPs材料在气体存储领域的理论体系，为实现室温存储氢气和俘获二氧化碳，提高PCPs材料在能源和环境领域的应用提供理论和实验依据。主要取得了如下研究进展：. （1）利用氰基化合物与叠氮化钠原位配体合成反应来合成富氮多孔晶态材料的过程中，我们发现通过控制氰基化合物与叠氮化钠的比例，能够揭示出四氮唑类化合物的合成反应机理，弄清过渡金属离子在反应中的催化作用，论文发表在顶尖杂志Angew. Chem. Int. Ed. 2015, 54, 11795-11799上。. （2）得到了两个以Zn-Li簇为结构节点的三维多孔配位聚合物，气体吸附测试表明它们能强烈地作用于H2分子和CO2分子，表现出很高的氢气和CO2吸附热，分别高达15.3和51.9 kJ/mol，此外，它们对CO2的吸附还具有很高的选择性，研究结果发表在Inorg. Chem. 2017, 56, 705−708上。. （3）利用溶剂热水热法还合成了系列孔表面功能化的多孔晶态材料，它们在气体存储与分离、光致发光、光致变色、药物控释等方面均表现出潜在应用前景，相关结果分别发表在Chem. Comm., Dalton Trans., CrystEngComm等上。. （4）依托本项目的研究，共发表SCI论文18篇，会议论文11篇，申请专利2项，授权1项；培养研究生5名，其中已经毕业2名，正在培养3名，培养本科生12名。