Synthesis And Catalytic Study Of New Photolysis Hydrogenatio Catalysts Based On Transition-Metal Substituted Polyoxometalates

In recent years,there is a strong need to develop earth-abundant photocatalytic materials for the extraordinarily large scale of solar energy utilization.Artificial photosynthesis for solar-driven evolution of H₂ from water represents a promising and desirable approach to sustainably provide clean and renewable fuel.Polyoxometalates?POMs?,as a typical class of metal-oxo clusters composed of earth-abundant elements,are particularly attractive as potential catalysts for water-splitting into H₂ and O₂ due to their ability to undergo fast,reversible,and stepwise multiple electron transfer reactions without changing their structures.Up to date,considerable progress has been made on using POM-based materials for visible light-driven water oxidation by introducing noble metal,and transition metal into laucunary POM units.However,most of the them use either strong UV-light or Pt?0?cocatalyst,its application still has certain limitation.Herein,two POM-Metal clusters have been synthesized by using nickel and[Sb₉W₂₁]and structurally characterized by the single crystal X-ray diffractions,thermogravimetry?TG?et al.methords.And on this basis,we also studied the catalytic photolysis hydrogenation propertities of crystals.1.Compound?NH₄?₉{Ni Sb₆O₄?H₂O?₃[Ni?hmta?Sb W₈O₃₁]₃}·?Hhmta?₆·5H₂O?1?was obtained by reaction of the Ni²⁺,?NH₄?₁₈[Na Sb₉W₂₁O₈₆]·24H₂O and hexamethylenetetra mine?hmta?under the aqueous solution.By changing the concentration of Ni²⁺and pH we can further obtain the chiral compounds?NH₄?₈Ni?H₂O?₆{Ni Sb₆O₄?H₂O?₃[Ni?hmta?S bW₈O₃₁]₃}·?Hhmta?₅·6H₂O?2?.2.After converting compound 1 to Tetrabutylammonium salt(TBA-Ni-Sb₉W₂₁),we studied the catalytic photolysis hydrogenation propertities of compound 1 with[Ir?dtbbpy??ppy?₂]PF₆ as photosensitizer,triethanolamine?TEOA?as sacrificial agent and LED light??=455 nm?as light source in the system of DMF/CH₃CN?V/V?=7/3 mixed solution.