PolyoxoNobleMetalate Chemistry Merged with Metal-Organic Frameworks: A Novel Class of Heterogeneous Catalysts

该项目的目的是以协同方式合并多金属氧酸盐（pom）和金属有机框架（MOFs）领域。聚甲醛是离散的阴离子金属氧化物，具有多种形状、大小、成分和相关性质。另一方面，mof是由金属离子或团簇组成的有序周期性网络，通过有机连接剂在三维空间中连接，形成空腔或孔。这里主要关注的是新型的多氧贵金属酸盐（ponm），如多氧酸盐（II）（由U. Kortz教授小组于2008年发现）及其与多孔mof的结合。ponm是离散的、阴离子的、溶液稳定的和空气稳定的贵金属氧化物，由方形平面配位的d8金属中心如Pd2+和Au3+离子组成，如pd13 -纳米立方[PdII13AsV8O34(OH)6]8- (Pd13As8)、pd15 -纳米星型Pd15P10、镧系和三维过渡金属中心纳米立方LnPd12和MPd12、Pd7V6纳米碗，以及混合贵金属钯金簇Pd8Au4。在中性或阳离子mof中加入这些ponm （ponm - mof）可以构建具有前所未有的催化性能的材料（例如非均相氧化/还原）。驻留在mof内的ponm可以进一步化学还原成单分散的纳米颗粒（钯、金、核壳或合金，取决于所使用的ponm），从而产生nanoparticle@MOF材料，这将是高活性的非均相催化剂。PONM还可以作为次级构建单元（SBUs），通过合适的有机连接剂和/或过渡金属离子连接，形成PONM集成MOF化合物（PONM- ofs）。这是一个新颖而开放的研究领域，它为实现多功能材料提供了巨大的潜力，特别是在多相催化领域。

The aim of this project is merging the areas of polyoxometalates (POMs) and metal-organic frameworks (MOFs) in a synergistic fashion. POMs are discrete, anionic metal-oxides with a multitude of shapes, sizes, compositions and associated properties. MOFs, on the other hand, are ordered periodic networks of metal ions or clusters connected in three dimensions by organic linkers to form cavities or pores. Here the major focus is on the novel class of polyoxo-noble-metalates (PONMs) such as polyoxopalladates(II) (discovered by the group of Prof. U. Kortz in 2008) and their incorporation into porous MOFs. PONMs are discrete, anionic, solution- and air-stable noble metal-oxides comprising exclusively square-planar coordinated d8 metal centers such as Pd2+ and Au3+ ions, e.g. the Pd13-nanocube [PdII13AsV8O34(OH)6]8- (Pd13As8), the Pd15-nanostar Pd15P10, the lanthanide- and 3d transition metal-centered nanocubes LnPd12 and MPd12, the Pd7V6 nanobowl, as well as the mixed noble metal pallado-aurate cluster Pd8Au4. Incorporation of such PONMs in neutral or cationic MOFs (PONM-MOFs) allows for the construction of materials with unprecedented catalytic properties (e.g. heterogeneous oxidations/reductions). The PONMs residing inside the MOFs could further be chemically reduced to form monodisperse nanoparticles (palladium, gold, core-shell or alloys, depending on the PONMs used) resulting in nanoparticle@MOF materials, which would be highly active heterogeneous catalysts. PONMs could also act as Secondary Building Units (SBUs) which can be linked by suitable organic linkers and/or transition metal ions, leading to the formation of PONM integrated MOF compounds (PONM-OFs). This is a novel and open field of research, which offers spectacular potential to realize multifunctional materials, especially in the area of heterogeneous catalysis.