ChemInform Abstract: Synthesis and Photocatalytic Properties of a New Heteropolyoxoniobate Compound: K₁₀[Nb₂O₂(H₂O)₂] [SiNb₁₂O₄₀]·12H₂O.

Abstract

Synthesis and Photocatalytic Properties of a New Heteropolyoxoniobate Compound: K10[Nb2O2(H2O)2][SiNb12O40]·12H2O. -The title compound is hydrothermally synthesized from a mixture of KOH, Nb2O5, Si(OEt)4, and ZrOCl2 in H2O (autoclave, 220°C, 24 h, 70% yield). K10[Nb2O2(H2O)2][SiNb12O40]·12H2O crystallizes in the tetragonal space group P42/mnm with Z = 2 (single crystal XRD). The structure contains anionic zigzag chains formed by [SiNb 12 O 40 ] 16α-Keggin clusters linked together via bridging [Nb2O2(H2O)2] 6+ units. The title compound exhibits overall photocatalytic water splitting activity which is significantly higher than that of Na10[Nb2O2][SiNb12O40]·xH2O -(ZHANG, Z.; LIN, Q.; KURUNTHU, D.; WU, T.; ZUO, F.; ZHENG, S.-T.; BARDEEN, C. J.; BU, X.; FENG*, P.; J. Am. Chem. Soc. 133 (2011) 18, 6934-6937, http://dx.

Metal–Oxyl Species and Their Possible Roles in Chemical Oxidations

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