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Nanjing Tech University develops highly efficient molecular sieve MOF membranes Author/Source: Sinochem News Network Date: May 16, 2023 Clicks: 18 On May 11, a team led by Professor Jin Wanqin from Nanjing Tech University, through interdisciplinary research combining mathematics, chemistry, materials science, and other fields, developed metal-organic framework (MOF) separation membranes with perfect lattice pores that enable efficient molecular separation. MOFs are a new generation of molecular sieve membrane materials, and creating MOF membranes with perfect lattice pores still presents significant challenges, with no breakthroughs having been achieved to date. Through interdisciplinary research combining mathematics, chemistry, materials science, and other fields, the team led by Jin Wanqin discovered that the problem of spherical close packing in geometry can be used to guide the creation of perfect MOF lattices and their separation membranes. They developed a probabilistic model to predict lattice defects and proposed a theory-based coordination strategy that increases the collision probability between organic ligands and metal clusters by controlling the film synthesis conditions, thereby creating perfect crystal film structures free of lattice defects. Using ultra-low-dose high-resolution electron microscopy imaging, they directly observed for the first time the lattice defects in the MOF membrane and its perfect lattice structure after those defects were eliminated. Experimental results show that the MOF membrane free of lattice defects allows only molecules smaller than the lattice pores to pass through rapidly, while molecules or ions larger than these pores are retained. This enables efficient separation of water and ions, as well as separation of methanol/dimethyl carbonate azeotropes with performance that is 1–2 orders of magnitude better than that reported in the literature, making it highly promising for industrial applications. The high-probability theoretical coordination strategy, inspired by geometry, not only enables the successful creation of perfect lattice pores and efficient molecular-scale separation but also provides a new approach for precisely manipulating lattice defects in order to control the size of sub-nanometer confined spaces and molecular transport. This work also provides a paradigmatic reference for exploring interdisciplinary research on advanced materials.