High Nuclear Polyoxometalates Based Composite Materials And Their Properties Research

Polyoxometalates(POMs), constitute of molecular metal-oxygen clusters (usually transition metal) with remarkable chemical, structural, and electronic characters, playing an important role in medicine, catalysis, or materials science. As the new members of the POMs, nanosized high-nuclear based POMs, have natural advantage to construct nano-materials and potentiality to be applied in many fields such as catalysis with their unique feature upon the small pieces of POMs.The high-nuclear based molybdenum-oxide based POMs of the wheel and ball type are successfully incorporated into nanotubes by the feasible LBL method via cation-anion electrostatic interactions with Keplerate type{Mo132} or Giant wheel type{Mo154} and polyelectrolytes on the inner pores of PC membrane template and their structures are proved maintaining in the nanotubes by a series of characterization. The nanotubes are as expected growing linearly as on the flat surface of quartz and the inside diameter and the wall thickness of the nanotubes can be well controled.Then this paper investigated the catalysis behavior of the derivatives of a Keplerate type POM{Mo132}, and originally used them as homo-and hetero-geneous to the degradation of an azo dye RhB by photocatalysis while the initial pH, weight of catalysis, concentration of dye and the recycling were investigated. Compound 2 which constructed by{Mo132} and TBAB showed great ability to degrade RhB. The{Mo132} was destroyed during the catalytic process but could be protected by organic such as TBAB and DODA to turn it from homo-to hetero-geneous. Based on the facts of the experiments, we inferred the mechanism of the heterogeneous photocatalysis that it's a OH radical generated reaction with oxygen enrichment in water solution and part of the catalytic process was on the surface of the catalysis.This paper points out a way to construct nano-devices with high-nuclear based molybdenum-oxide based POMs of the wheel and ball type which have already revealed extensive intriguing and important physical and chemical properties and the photocatalysis of the derivatives of a Keplerate type{Mo132} we discuss here expand the application of high-nuclear based POMs.