(687e) Incorporation of a Dioxo-Molybdenum(VI) Complex into a Titanium-Functionalized Zr(IV)-Based Metal-Organic Framework

Metal-Organic Frameworks (MOFs) are very porous, crystalline and well-ordered materials that can be used in different applications such as catalysis, gas adsorption-desorption, and photocatalysis among others due to their properties [1]. Therefore, it is not surprising that many researchers are studying the design, synthesis and surface modification of new types of MOF [2]. In fact, recent studies have focused on the synthesis of new MOFs based on titanium as a substitute for titanium dioxide for photocatalytic applications [3-5]. However, these studies have reported different problems mainly due to the use of the metal precursor, in that sense, in many cases, it is not possible to obtain a porous material, or the obtained product is TiO₂ [1]. Nowadays, the possibility of a metal exchange using an ion exchange within a Zr-MOF to build a material that combines the properties of both metals seems highly promising [6]. These new Zr/Ti-MOFs should be used as supports for the immobilization of a Mo(VI) catalyst [7, 8]. In consequence, such materials have the potential to catalyze the epoxidation of alkanes using UV-Vis irradiation, and molecular oxygen as an oxidizing agent, which is quite challenging [9, 10]. In this work, the synthesis of new Ti-MOFs that incorporated a dioxo-molybdenum (VI) complex was studied. First, a molybdenum complex was anchored to a bipyridine-dicarboxylate ligand, which was then immobilized in a UiO-67-type MOF. Finally, Ti⁺⁴ ion exchange was performed at Zr⁺⁴ of the Zirconium MOF nodes. This material was characterized by sorption of N₂, XRPD, FTIR, RAMAN, TGA, XPS, atomic absorption and SEM analysis.

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