title: Metal substitution in a Lindqvist polyoxometalate leads to improved photocatalytic performance.
abstract: The photochemical properties of homo- and heterometallic molybdate-based Lindqvist polyoxometalate clusters are investigated in a comparative study and it is shown that vanadium substitution can be used as a facile synthetic tool to optimize the visible light absorption and photocatalytic activity of the cluster. The mono-vanadium substituted unit, [VMo(5)O(19)](3-) shows light absorption up to 480 nm whereas the light absorption of the molybdate analogue [Mo(6)O(19)](2-) is mainly in the UV region below 400 nm. The electronic absorption properties of both clusters are further investigated using TD-DFT calculations which show that vanadium incorporation leads to the formation of low-energy O → V LMCT transitions. In comparative photochemical dye decomposition test reactions under UV and Vis irradiation, a higher reactivity is observed for [VMo(5)O(19)](3-) together with turnover numbers of more than 1600. In addition it is shown that under anaerobic conditions, the photoreaction proceeds faster than in the presence of oxygen, suggesting that oxygen acts as a quencher in one of the photoredox steps.
authors.affiliation: Friedrich-Alexander-University Erlangen-Nuremberg, Department Chemistry and Pharmacy, Institute of Inorganic Chemistry II, Egerlandstr. 1, 91058 Erlangen, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Tucher
authors.forename: Yanlin
authors.initials: Y
authors.lastname: Wu
authors.forename: Leanne C
authors.initials: LC
authors.lastname: Nye
authors.forename: Ivana
authors.initials: I
authors.lastname: Ivanovic-Burmazovic
authors.forename: Marat M
authors.initials: MM
authors.lastname: Khusniyarov
authors.forename: Carsten
authors.initials: C
authors.lastname: Streb
mesh_terms: D002384:Catalysis; D056831:Coordination Complexes / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D017973:Tungsten Compounds / Q000737:chemistry*; D014466:Ultraviolet Rays; D000099294:Polyoxometalates
chemical_list: D056831:Coordination Complexes; D008670:Metals; D017973:Tungsten Compounds; C102296:polyoxometalate I; D000099294:Polyoxometalates