Dispersion of metal oxide nanoparticles in conjugated polymers: investigation of the TiO_2/ppv nanocomposite

摘要

It 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 TiO_2/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 reversible quench the PL emission, thus suggesting enhanced gas sensing properties. A tentative mechanism explaning the role of n-TiO_2 is briefly discussed.