新颖多铌氧酸盐的结构调控及净化甲基膦酸二甲酯研究

As an important branch of polyoxometalates (POMs), polyoxoniobates (PONbs) have unique topological structures and potential applications in catalysis, bionics and multi-functional materials. However, due to the lack of soluble precursors, the relatively inert chemical reactivity of niobium, the narrow reaction pH (10.5-12) and the limitation of integration technologies, the research on the synthesis and properties of PONbs is still yet to be developed compared with the development of polyoxovanadates (POVs), polyoxomolybdates (POMos) and polyoxotungstates (POWs). In this project, we intend to a) construct novel PONbs with high nucleus, giant mixed type and giant novel configuration through the regulation and control of synthesis strategy, and determine the relationship between novel structures and regulations; b) study the performances and mechanism of decontamination of dimethyl methylphosphonate (DMMP) by novel PONbs, and determine the relationship between the catalytic performances and the cations, active polyanions and negative charge density in the structure of PONbs; c) integrate PONbs on the surfaces of large porous single crystals by in-situ inducing, study the novel methods for the integration of PONbs/large porous single crystal and the decontamination of DMMP, determine influences of the composition, microstructure and the interface on catalytic properties, and develop novel PONbs with more efficient catalytic properties. The aim of the project is to develop the structures of PONbs, to lay a foundation for the development and application of novel PONbs-based functional materials, and to promote the development of structural chemistry of POMs finally.

铌多酸（多铌氧酸盐）作为多酸领域一个重要分支，具有独特的拓扑结构且在催化、仿生学和多功能材料等方面具有潜在的应用价值。然而，由于可溶铌盐种类的缺乏，铌自身的惰性，狭窄的反应pH值(10.5-12)及集成方法的限制，新颖铌多酸的合成与性能研究与钒、钼、钨多酸相比依然尚待发展。本项目拟通过调控合成策略，构筑新颖高核数、巨型混合型、巨型构型新奇的铌多酸，确定新颖结构与合成调控关系；研究新颖铌多酸催化净化甲基膦酸二甲酯的性能与机制，确定催化性能与铌多酸结构中抗衡阳离子、活性聚阴离子和负电荷密度的关系；通过多孔大单晶表面诱导原位生长铌多酸，研究新颖铌多酸/多孔大单晶复合体系集成的方法及催化净化甲基膦酸二甲酯性能，确定复合体系组分、微结构及界面对催化性能的影响，发展具有高效催化性能的新颖铌多酸材料体系。项目旨在发展铌多酸结构，为新颖铌多酸基功能材料的开发和应用打下基础，促进多酸结构化学的发展。

晶体材料的设计合成研究是无机合成化学及材料领域具有重要意义的研究课题之一。多酸晶体材料具有丰富的拓扑结构，在催化领域具有重要的潜在应用。大尺寸多孔单晶兼具长程有序晶格结构和无序连通孔道结构的特点，在研究催化反应中的表界面结构及催化机制呈现了显著优势。本项目主要探索了上述材料的合成、理化性质、催化机理及性能增强机制方面的研究，主要结果如下: 1) 通过晶格重构策略，生长出系列2cm尺寸的多孔氮化钽单晶，作为光电阳极表现出相对于传统材料显著增强的光电性能及优异的光电化学氧化醇制醛/酮性能，同时结合理论计算研究了催化机理及催化性能与表界面结构的关系；2）通过晶面工程，提高了多孔氮化钽单晶的载流子迁移率，降低了在中性溶液中的起始电位，增加了氮化钽的ABPE值、光电化学性能及化学稳定性；3) 通过配位不饱和策略构建了系列多孔金属氮化物单晶材料，并探索研究了扭曲表面的配位不饱和金属-氮活性位点增强的电催化活性规律；4) 通过合成探索获得不同于传统钒类催化剂的氮化钒多孔单晶和系列具有可控氧化态的氧化钒单晶，该系列多孔单晶结构增大了反应面积并提高了催化活性，展现了有效的乙烷脱氢性能；5) 探索生长了一种尺寸为0.1 cm ~ 30 cm的锐钛矿型二氧化钛致密单晶材料，其生长方法操作简单、重复性好、价格低廉、可规模化生产，是最重要的半导体之一。本项目研究同时拓展了系列新颖晶态材料的设计合成与性能研究，对新型功能晶体及其复合材料的开发和应用具有重要的意义。本项目在国际知名期刊发表论文9篇，获得授权发明专利1项。