高稳定MOFs的设计合成及其在甲烷储存中的应用

In natural gas storage, the key of using the “adsorption natural gas” technology is the adsorbent selection. Metal-organic frameworks (MOFs), as a type of novel adsorbent have great application prospect in natural gas storage. Where, the stability and the methane adsorption storage capacity are the keys for their practical application. However, the preparation of robust MOFs with both high stability and high methane storage capacity is challenging to date. On the basis of our previous work in related topics, this project is going to study the rational design and synthesis of several kinds of highly stable MOFs and their application in methane storage, to obtain new adsorbents with good natural gas storage ability. In the study, taking the stability of MOFs and their methane adsorption efficiency as the guidance, starting from the chemical bond nature and molecular level design, we will work on three series of stable MOFs systems and use three design strategies to improve the methane storage capacity of them. We study the synthetic conditions, molecular structures, framework and hydrothermal stability, pore properties, and methane adsorption capacity of these new MOFs; investigate the relationship between the structure and stability, involved coordination bond and stability, and the structure and methane adsorption ability of them; explore the effect of some special functional groups in MOFs on their methane adsorption ability; as well as check the material recycling. Based on these results, we expect to conclude some general rules in synthesizing stable and robust MOFs and in efficiently tuning their methane storage capacity, as well as to further understand the methane adsorption mechanism in MOFs and the balance of various factors which affect the methane storage of MOFs. The results from this project would promote the exploration of new methane storage materials, and the development of MOFs applications in various fields. The related results are also important and useful in guiding the target design and synthesis of other porous materials for particular applications.

“吸附储存天然气”技术应用的关键在于吸附剂选择。MOFs作为一类新型吸附剂，在天然气储存中有极大应用前景。其稳定性和甲烷储存能力是有用与否的关键，但制备高稳定且高甲烷储存能力的MOFs极具挑战。本项目拟在申请人原有工作的基础上，研究几类高稳定性MOFs的设计合成及其在甲烷储存中的应用，开发新吸附剂。研究中以稳定性和甲烷吸附功效为导向，从化学键本质和分子层次设计入手，着手于三个高稳定MOFs体系，并通过三种策略提高其甲烷储存能力。研究其合成条件、结构特征、框架与水热稳定性、孔性质、甲烷吸附能力；成键及结构与材料的稳定性、结构与甲烷吸附能力间的关系；特殊功能团对甲烷吸附的影响；及材料的循环使用等。探索合成高稳定MOFs及调节其甲烷储存能力的一般规律，理解甲烷吸附机理及各因素的平衡关系。研究成果将对甲烷储存材料开发和MOFs的应用探索具有推动作用，也对探索其他孔材料的定向设计与合成具有指导意义。

金属有机框架（Metal-Organic Frameworks, 简称MOFs）作为一类新型多孔功能材料，在气体储存、分离、催化、传感等众多方面表现出极大的应用潜力。但由于配位键的本质特征，大部分MOFs的化学稳定性，尤其是水及酸碱稳定性较差，严重制约了这类新材料的实际应用。本项目在前期工作的基础上，研究了几类高稳定MOFs的设计合成方法，提出了这类材料稳定性调控策略，成功制备了20多种结构稳定孔结构各异的新型MOF材料，并探索了这些材料的甲烷存储，气体分离、污染物去除与传感等方面的性能表现，得到了一些重要结果，例如，通过使用强配位键、提高结构对称性、增加配体疏水性和控制配体刚柔性程度多策略并用实现了系列高稳定MOFs的构筑；在构筑高稳定MOFs的同时，设计MOFs的孔道表面的组成与结构，提升材料的性能表现，如对特定分子的吸附亲和力，质子导电性和荧光响应性。本项目还在研究内容上进行了拓展，例如，发展了取向纳米阵列辅助成膜方法，可控制备了多种气体分离性能良好的MOF薄膜；将在水中稳定且分散性良好的MOF材料与聚合物混合制备成杂化膜用于纳滤分离水中染料等污染物；制备了系列MOF衍生物，催化功效良好。在本项目资助下，研究结果迄今共发表学术论文44篇，其中SCI收录论文43篇（影响因子大于10的一区论文17篇），部分论文发表在Nature Energy, Nature Commun., Chem, J. Am. Chem. Soc., Adv. Mater., Chem. Rev., Chem. Soc. Rev.等期刊上；参编专著章节3章，申请中国发明专利21项。项目执行期间，项目负责人获中国石油和化学工业联合会青年科技突出贡献奖、茅以升北京青年科技奖、亚洲杰出科研工作者和工程师奖等；入选国家“万人计划”科技创新领军人才、青年北京学者；2017、2018、2019年入选“全球高被引作者”。培养博士后3名、博士生7名、硕士生8名。