高吸氢吸附焓氮杂环纳米孔有机聚合物的研究

With regard to low hydrogen adsorption enthalpy (4-7kJ/mol) of nanoporous organic polymers (NOPs) as well as their poor hydrogen storage capacity under ambient condition, the purpose of this project is to design and experimentally develop a novel series of three-dimensional aza-heterocyclic NOPs from the perspective of molecular design, having a hydrogen adsorption enthalpy of 10-20KJ/mol based on activation technologies. The activation technologies applied include the incorporation of electron-rich aromatic units and the transition metal ions doping of NOP backbone that has a high specific surface area and pore volume. The relationship of structure-property is also studied. Tetrahedral monomers namely tetrakis(4-cyanophenyl silane) are used as precursors to build a series of aza-heterocyclic NOPs, to study the synthetic rule and pore tailoring strategies.This project is mainly focusing on the influence of molecular structure and topology of NOPs on their hydrogen absorption properties. Active Fe2+ is incorporated by the copolymerization chemistry of 1,1'-bisferrocene dinitrile and tetrahedral monomers, and the influence of the monomer composition and polymerization conditions on pore structure, microcosmic structure as well as morphology of NOPs was also investigated. This study leads to a systematically research on the structure-property relationship and would acheive an appropriate regulation of the hydrogen storage performance, which would be helpful for guiding the design and preparation of nanoporous organic polymers with high hydrogen adsorption enthalpy and high hydrogen capacity.

针对纳米孔有机聚合物（NOPs）吸氢作用力较弱（吸附焓4-7kJ/mol）及室温储氢量较低等问题，本项目拟从分子设计角度出发，将富电子芳香单元构筑到具有高比表面积和孔容及优异稳定性的三维氮杂环NOPs骨架上，并键合过渡金属来对其进行修饰，创制具有较高吸附焓（10-20KJ/mol）的储氢材料，研究其结构-性能关系。选择具有四面体拓扑结构的四（4-氰基苯基）硅烷等为前驱体，构筑系列氮杂环NOPs，研究其合成规律和孔结构调控策略，重点研究富电子芳香单元对吸氢性能影响规律；通过加入1,1'-二茂铁二甲腈共聚引入Fe2+修饰氮杂环NOPs，研究聚合条件、金属离子含量对NOPs孔结构和微观结构的影响规律；系统研究NOPs分子结构、孔结构与微观结构对吸氢吸附焓的影响规律，从而深入研究NOPs储氢材料的结构-性能关系，实现储氢性能的适度调控，为高吸氢吸附焓及高储氢性的纳米孔聚合物的设计及制备提供新思路。

近年来纳米孔有机聚合物由于其高比表面积、轻质的骨架构造、丰富的构建与改性方法，被广泛应用于气体分离、药物缓释和重金属离子吸附等方面。1,3,5-三嗪作为一类特殊的芳香杂环单元，因具有较高的电子效率/平面共轭结构及热化学稳定性，可作为纳米孔有机聚合物的理想构筑单元。本课题基于1,3,5-三嗪结构单元设计构筑了系列纳米孔有机聚合物，并探索了其在气体分离、重金属离子处理等方面的应用。.1..设计合成含极性杂环结构的芳香二腈单体，采用改进的离子热法克服了芳腈聚合时易分解的缺点，制备了系列1,3,5-三嗪基纳米孔有机聚合物。聚合产物具有高的热稳定性和小分子气体吸附能力；通过3,6-二氰基咔唑N-H的取代反应，引入甲基、乙酸乙酯基、苯基等，采用bottom-up策略聚合可进一步调控聚合物孔结构和吸附性能。.2..设计合成了高活性的1,3,5-三嗪基氰酸酯，经二苯砜溶剂热缩合反应，成功制备了NOP-14；其对药物分子布洛芬有较好的吸附能力，单位质量的聚合物吸附量达到386 mg/g，且表现出良好的释放动力学。.3. 设计经二苯并呋喃和二苯并噻吩分别与三聚氯氰发生F-C反应，制备了富含杂原子的纳米孔有机聚合物，比表面积分别可达432 m2/g和55 m2/g。结果表明，该合成方法简便高效，产物对Hg2+表现出快速高效的吸附（最大吸附量可达604 mg/g）。此外，FHPTs和THPTs对Hg2+有明显的荧光淬灭响应，在重金属离子的吸附及检测领域具有诱人的应用前景。