晶态多孔材料的功能化构建宽温域高性能质子导体材料

On-board fuel cell technology requires proton conducting materials with high conductivity not only at intermediate temperatures for work, also at room temperature and even subzero temperature for startup when exposed to the colder climate. To develop such materials meets the requirements of National Energy Development Strategy Action Plan (2014-2020), but it is still challenging because many promising candidates, including Nafion materials, for the proton transport on basis of extended microstructures of water molecules suffer from significant damage by heat at temperatures above 80 oC or by freeze below -5 oC. Crystalline porous materials (CPMs) show exceptional promise in the proton conductors due to their structural and chemical tunability. CPMs can provide abundant structural information to visualize the proton medium within pores and to reveal their specific proton transport via diffraction experiments, and can make better conductor design enabled via further pore adjustment and functioalization. But there are some serious issues for CPMs conductors: low stability; the performance for the CPMs with aqueous media more replies on the water content, while those with non-aqueous media exhibit relatively low conductivity; and no obvious proton conducting behaviors was observed at subzero temperature heretofore. In order to target the title materials, first, this proposal will employ the polyimide-base porous organic frameworks, or clad the CPMs with the second materials, such as graphene oxide, layered materials, polymers and even other CPMs to figure out the CPMs’ stability. Second, this proposal will develop three various avenues: the embedding of nanoparticles into the pore of CPMs, the searching of new types of non-aqueous proton medium with high melting points and small pKa, and the functionalization of the skeletons to match the size effect, to design the stable proton transport pattern for the improving proton conductivity over the wide temperature from subzero to moderate temperature. Once it is achieved, we would build up the rules of the relationships between the structures of CPMs and the proton conductivity. This kind of CPMs could show both high stability and high conductivity over wide temperature as long as we adjust the hosts and guest medium via the post-synthetic functionaliztion of the CPMs. Once the project is completed, we may publish 8 - 10 peer-reviewed papers in decent journals and file 3 - 5 patents.

宽温域质子导体是车载燃料电池核心技术，其研发符合国家能源发展战略行动计划(2014)的需求。相较于Nafion材料因水依赖性强带来工作温域窄等不足，基于晶态多孔材料(CPMs)的新型质子导体材料在结构调控、性能调节和机理研究上彰显优势，但存在未实现零下温度工作、稳定性差、水媒介CPMs对水依赖高、非水媒介CPMs质子导电率低等问题。本项目首提宽温域(-40~200 oC)质导材料，从结构设计出发，针对性展开CPMs功能化研究：①以聚酰亚胺类有机多孔聚合物为骨架，和包覆复合方法增强骨架稳定性；②提出纳米粒子孔道功能化、高熔点非水质子媒介物、尺寸匹配骨架功能化等方法，促进质子生成，设计稳定质子传递通道，提高宽温域质子导电率。建立CPMs质子导体构性关系规律，解析质子传递机理；通过反馈式合成，优化材料，构建高稳定性、宽温域和高质导率的CPMs材料。预期申请专利3~5项，发表SCI论文8~10篇。

针对当前燃料电池中使用的Nafion全氟磺酸质子交换膜，基于水介质基的质子传导机理，既无法在中高温度工作，以避免必要的铂催化剂的CO中毒，也无法在零下温度正常启动以满足车载技术在寒冷地区的应用的问题，(a)我们首创性提出发展宽温域高质导材料，以满足燃料电池汽车的需求。提出高熔点质子载体有助于实现宽温域的稳定质子传输途径，在国际上率先实现从零下到中温区的宽温域高质导材料；(b) 自主搭建了一套集合低温探针平台、阻抗谱仪、铁电仪、源测量仪和LCR Meter的单晶电介质测试系统；(c) 论证了调节金属离子节点是一种不改变质子传递路径，也能显著提高材料质子导电性的有效策略；(d) 金属环有机框架构筑高质导材料；(e) 柔性MOFs封装筛选质子媒介物，以获得宽温域高质导的材料；(f) 一步法蒸载咪唑获得宽温域高质导的材料；(g) 主客体相互作用法获得高OH-传导的材料； (h) 装载酸碱对法获得宽温域高质导的材料；(i) 穿插程度控制多孔材料的质导性能；(j) 包封染料提升MOFs的质子导电率；(k) 溶剂辅助改性法提升质子传导性能; (l) 内表面修饰非配位羧酸提升六柱柱撑金属-有机纳米管的质子导电性; (m) 集合阻变和整流效应的质子传导MOFs基阻变存储器。项目建设期内，培养硕士研究生10名，承办和协办国内会议3次，受邀参加中国化学会年会等会议作邀请报告9场次，邀请国内外同行专家来访讲学79人次，在Science Advances，J Am Chem Soc(4篇)，ACS Applied Materials & Interfaces、J Mater Chem A、Inorg. Chem. 等期刊发表论文38篇，受邀撰写Adv Mater一篇题为Metal-Organic Frameworks as a Versatile Platform for Proton Conductors的综述(Progress Report, No. adma.201907090R2，已接受)，申报中国发明专利16件，授权1件。团队入选福建省研究生导师团队和福建省高校科技创新团队。项目负责人荣获第十三届福建青年五四奖章，入选校“宝琛计划”高端人才、福建省杰出青年科学基金，并获得滚动支持。