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Updated: Nov 27, 2025
Preparation of Polyoxometalate-based Photo-responsive Membranes for the Photo-activation of Manganese Oxide Catalysts
Published on: August 7, 2018
Crystal structure and photophysical properties of a novel polyoxomolybdate porphyrin
1Institute of Applied Chemistry, School of Chemistry and Chemical Engineering, Jian Key Laboratory of Photoelectric Crystal Materials and Device, Jiangxi Province Key Laboratory of Coordination Chemistry, Humic Acid Utilization Engineering Research Center of Jiangxi Province, Jinggangshan University, Jian, Jiangxi 343009, Peoples Republic of China, State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, Peoples Republic of China, and Department of Ecological and Resources Engineering, Fujian Key Laboratory of Eco-industrial Green Technology, Wuyi University, Wuyishan, Fujian 354300, Peoples Republic of China.
Abstract:
A novel polyoxomolybdate with a diprotonated porphyrin as counter-cation, namely, 5,10,15,20-tetrakis(4-carboxyphenyl)-21H,22H,23H,24H-porphine(2+) hexamolybdate(VI) pentahydrate, (C48H32N4O8)[Mo6O19]·5H2O or (H2TCPP)[Mo6O19]·5H2O, I, was prepared via the hydrothermal reaction of MoCl5, 5,10,15,20-tetrakis(4-carboxyphenyl)-21H,23H-porphine (TCPP) and distilled water. The crystal structure of hydrated polyoxometalate (POM) salt I was characterized by single-crystal X-ray diffraction. The compound is characterized by an isolated (zero-dimensional, 0D) structure, because it cannot extend via covalent bonds. The structure contains one [Mo6O19]2- anion, one (H2TCPP)2+ cation and five lattice water molecules. Each of the Mo6+ ions is six-coordinated and displays a distorted octahedral motif. The (H2TCPP)2+ cation displays a distorted saddle motif. A three-dimensional (3D) supramolecular framework is formed via hydrogen-bonding interactions. The compound shows a red photoluminescence emission.
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