Syntheses And Photodegradating Activity Studies Of Octamolybdate-based Isomers Inorganic-organic Hybrids

The POMs-based inorganic-organic hybrid compounds are constructed from metal complexes or organic cations and POMs building blocks,which widely applied in fields of catalysis,medicine,optics,electronics and magnetism.In this paper,we choose the high moisture sensitivity of MoCl5 as the molybdenum source.Four Octamolybdate-based hybrid compounds have been hydrothermally synthesized.When introducing transition metals Co2+ and 1,10-phenanthroline into the mixture with NaOH solution or KOH solution to adjust pH to about 7.0,we can obtain respectively two compounds: [Co?phen?₃]2H4[NaO?H2O?(?-Mo₈O₂₆)]2·2H2O?1?and [Co?phen?₃]4H4[?-Mo₈O₂₆][?-Mo₈O₂₆]2[Mo₆O₁₉]Cl2·18H2O?2?.Compound 1 is the first dimeric structural compounds of the novel ?-[Mo₈O₂₆]4-linked by alkali metal Na+.Compound 2 is the first one containing both two diffeerent [Mo₈O₂₆]4-isomers and [Mo₆O₁₉]2-.When introducing 4,4?-bipyridine into the mixture and adjusting p H to about 5.0,we synthesized another compound:?C10H10N2?2[?-Mo₈O₂₆]?3?;When introducing transition metals Ni2+ and 1,10-phenanthroline into the mixture and adjusting pH to about 7.0,[Ni?phen?2]2(?-Mo₈O₂₆)?4?was obtained.Furthermore,we have carried out a series of characterization for these four hybrid compounds,and find that they all have relatively lower band gap and could act as potential semiconductor materials.Therefore,we have carried out the photodegradating dyes research of them,discovering that compound 3 and 4 have good response for visible light,so they can act as effective photocatalysts.By investigating,these two compounds all achieve the purpose of degrading organic dyes methyl orange?MO?under visible light irradiation,indicating excellent photocatalytic activity.