Multifunctional Multilayer Films Containing Polyoxometalates and Bismuth Oxide Nanoparticles

Abstract

Multifunctional multilayer films consisting of the Keggin-type polyoxometalate [SiW(9)V(3)O(40)](7-) (SiW(9)V(3)) and bismuth oxide nanoparticles (Bi(2)O(3)) were prepared by the layer-by-layer assembly method. For the first time, electrochromic and photochromic studies were done on a film containing both polyoxometalates and nanoparticles. The films were characterized by UV-vis absorption, emission spectra, and atomic force microscopy. Their electrochromic and photochromic properties were investigated by cyclic voltammetry and UV-vis spectroscopy. The results show that the reduction of SiW(9)V(3) is very reversible and tunable with the addition of Bi(2)O(3) layers into the film. The electrocatalytic activity of the films toward oxidation of l-cysteine hydrochloride hydrate (l-cysteine) and reduction of nitrite were studied with cyclic voltammetry. The results show that the incorporation of Bi(2)O(3) nanoparticles into the films changed the films' photoluminescence properties and electrocatalytic efficiency.

Generation and photocatalytic activities of Bi@Bi2O3 microspheres

“…the UV-vis spectrum showed an absorption peak centered at about ~294 nm in wavelength (4.21 eV in photon energy). This result is similar to the values for Bi 2 O 3 reported by Li and Wan [54,55].…”

Preparation and visible-light photochromism of phosphomolybdic acid/polyvinylpyrrolidone hybrid film

“…Polyoxometalates(POMs) are a unique class of inorganic metal-oxide clusters and have been proved to be an attractive class of photochromic materials due to the ability of accepting one or more electrons to yield mixed-valency colored species(heteropolyblues or heteropolybrowns) [4][5][6][7][8] . Nowadays, many photochromic materials based on POM embedded into polymeric networks via non-covalent bonding were prepared, which improved the physical and chemical performance of hybrid films significantly [9][10][11][12] . Varieties of organic or inorganic polymers were used as matrix to construct hybrid films, such as polyacrylamide [13,14] , polyvinyl alcohol [15,16] and polyether chains [17,18] .…”

Polyoxometalates in Polyelectrolyte Multilayer Films: Direct Loading of [H7P8W48O184]33– vs. Diffusion into the Film

“…[21] Many films have been produced incorporating nanoparticles and among these studies are some using POMs as the inorganic building block. [22][23][24][25][26][27][28] The possible application of POM-containing PEM films as electrochromic and photochromic materials has already been demonstrated. [23e,28] 33-may have very interesting electrocatalytic properties [29] as well as electrochromic properties.…”