![]() The simulated pattern fit well to the experimental pattern after Rietveld refinement, indicating that the proposed structure was correct and that there were no obvious crystalline impurities (Supplementary Fig. The 8− units were proposed to be connected by VO 2+ linkers to form a 3D framework. The arrangement of W formed 8- cubane cluster 20. ![]() The initial structure was solved by the charge-flipping algorithm (Supplementary Table 3). The XRD pattern of VT-1 was indexed to a cubic cell with lattice parameters of 17.1101 Å and a space group of PA-3 (Supplementary Table 2). The redox-active transition metal oxide porous framework exhibits high catalytic activity in the selective reduction of NO by NH 3. The micropores are opened, and the materials adsorb a variety of small molecules. The structures of the new materials are confirmed by powder X-ray diffraction (XRD), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and X-ray absorption near-edge structure (XANES) analysis, showing that different arrangements of the units and linkers form porous frameworks with LTA and IRY topologies, respectively. The structural prediction reveals the two most stable frameworks, which are able to be synthesized accordingly. The VT family is constructed by connecting cubane clusters, 8−, with VO 2+ linkers to generate various isomeric frameworks. Here, we report the synthesis of a new family of zeolitic transition metal oxides based on vanadotungstate ( VT), which successfully combine a transition metal composition and porosity with high structural and property tunability. Therefore, new progresses in obtaining zeolitic materials with all-transition metal oxides that would increase the diversity of material design are strongly desired by material scientists. However, the current materials suffer from problems that include poor structural diversity, unopened micropores 18, and low surface area and porosity 18, 19. The typical materials are porous frameworks based on ring-shaped unit 14, 15, unit 16, and pentagon units 17. There are only a few examples of zeolitic transition metal oxides. However, these approaches are not effective for introducing transition metals with a high content, precise locations, and well-ordered structure.Ī more inventive method for forming a porous framework is the direct assembly of transition metal ions via a bottom-up approach, particularly using polyoxometalates (POMs) as cluster precursors 13. The classical methods to achieve this kind of combination is the direct modification of zeolites through ion-exchange 9, modifying the framework disorderly 10, and forming mixed tetrahedral and octahedral frameworks 11, 12. With the combination of the unique properties of transition metals with ordered microporosity, major breakthroughs in applications have been achieved 6, 7, 8. Transition metal elements have superior properties including redox, photochemical, electrochemical, and magnetic properties due to partially occupied d-orbitals, which enable catalytic functions and applications that main group elements cannot achieve. The combination of properties derived from the composition with the specific porous structure is more important for the future development and application of zeolitic materials in catalysis. On the other hand, the composition of zeolites is still limited to a few main group elements, such as Si, Al, P, B, and Ge, which hinders the further development of zeolites. To date, hundreds of zeolitic frameworks with a variety of ordered microporous topological structures have been discovered 1, 2, 3, 4, 5. Zeolites, microporous crystalline aluminosilicates, are inorganic functional materials that have wide applications in catalysis, because of their well-defined structures, complex pore systems, thermal stabilities, and high surface areas. This finding provides an opportunity for design and synthesis of inorganic multifunctional materials for future catalytic applications. ![]() Owing to the complex redox properties and open porosity, the vanadotungstates efficiently catalyse the selective reduction of NO by NH 3. The assembly of 8− units with VO 2+ forms two isomeric porous frameworks. Here, we report a new class of zeolitic vanadotungstates with tunable frameworks exhibiting a large porosity and redox activity. ![]() However, the examples of zeolitic transition metal oxides are rare. Another promising choice is zeolitic transition metal oxides providing both porosity and redox activity, thereby further expanding the diversity of porous materials. Zeolites are limited to main group elements, which limits their applications in redox catalysis. Developing new zeolites is one approach towards this design because of the tunable pore system and high thermal stability. Design of the structure and composition of crystalline microporous inorganic oxides is of great importance in catalysis. ![]()
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