Dispersion Of Metal Oxide Nanoparticles Research Articles

Hexadecyltriethoxysilane-induced Dispersions of Metal Oxide Nanoparticles in Nonpolar Solvents

Nanoparticles of CeO2, Fe3O4, TiO2 and ZnO get coated by hexadecyltriethoxysilane on refluxing the nanoparticles and the organosilane in a hydrocarbon solvent. The organosilane-coated metal oxide nanoparticles give stable dispersions in hydrocarbon solvents due to their hydrophobic surface. On heating in air, the organosilane-coated metal oxide nanoparticles yield to silica-coated core-shell type nanoparticles.

Anti-reflective optical coatings incorporating nanoparticles

This paper presents a simple approach for forming anti-reflective film stacks on plasticsubstrates employing aqueous colloidal dispersions of metal oxide nanoparticles. Resultsdemonstrate that it is possible to fabricate a polymeric thin film of continuously tunablerefractive index over a wide range by loading the film with varying concentrationsof metal oxide nanoparticles. Specifically, the refractive index for the polymerfilm was tuned from 1.46 to 1.54 using silica nanoparticle loadings from 50 to0 wt% and from 1.54 to 1.95 using ceria nanoparticle loadings from 0 to 90 wt%,respectively. The low and high refractive index layers are then combined to create ananti-reflective coating which exhibits a reflectance spectrum, abrasion resistance, haze andtransmission values that compare well with those produced using state-of-the-art vacuumbased techniques. Furthermore, the results show that it is possible to begin withaqueous dispersions and then dilute them with organic solvents for use in a spincoating method to prepare the polymer–metal oxide nanoparticle composite films.

Dispersion of Metal Oxide Nanoparticles in Conjugated Polymers: Investigation of the Tio2/PPV Nanocomposite

ABSTRACTIt is well established that the dispersion of nanosized metal particles in a polymer matrix can induce non linear optical properties, yet very little is known about the effect of semiconducting transition metal oxide nanoparticles on both electrical and luminescence properties of conjugated polymers. In this paper, we report the synthesis of a nanostructured TiO2/poly(pphenylenevinylene) system and show by diffuse reflectance infrared Fourier transform spectrometry (DRIFTS) that a stable conjugated nanocomposite is obtained. Investigation of the photoluminescence (PL) properties reveals both a broadening and a blue shift of the emission spectra. Adsorption of oxygen is found to be stronger on the nanocomposite than on PPV and to reversibly quench the PL emission, thus suggesting enhanced gas sensing properties. A tentative mechanism explaining the role of n-TiO2 is briefly discussed.