Three New Polyoxoniobates Functioning as Different Oxidation Catalysts

Three new multifunctional isopolyniobates based on {Nb24O72}, namely, [Cu(en)(2)](9.75)[Cu(en)(2)(H2O)](4)[KNb24O72H9.25](2) center dot 36.5H(2)O (1), [Cu(en)(2)] [Cu(en)(2)(H2O)](12)[Cu(en)(2)(H2O) 2] 3[KNb24O72H7(H2O)(2)](2)center dot 99H(2)O (2), and [K(H2O)(4)][Cu(en)(2)(H2O)(2)](5)[Cu(en)(2)(H2O)](8.25)[Cu(en)(2)](2)[K0.5Nb24O72H7.75](2) center dot 115.31H(2)O (3) (en = ethylenediamine), were obtained and characterized by IR, powder X-ray diffraction, single-crystal diffraction analysis, etc. Single-crystal analyses of the three compounds shows that all their clusters exhibit the same bowl-shaped structure, while the different transition metal complexes (TMCs) make compounds 1-3 show three entirely different packing structures. The catalytic properties of the three compounds as catalysts for Rhodamine B (RhB) photocatalytic degradation, styrene oxidation, and oxygen evolution reaction (OER) have been assessed, and all the compounds have good catalytic effects on the three different catalytic processes.