Preparation of CeO2-PVA composite film based on in-situ generation of nano CeO2 particles

Abstract

In order to prepare nano CeO2-Polyvinyl alcohol (PVA) composites, obtaining composite materials with specific performance generated by the synergistic effect of organic and inorganic component, and to simplify the composite process and improve the dispersion uniformity of inorganic particles in the polymer matrix, a cerium-triethanolamine complex was used as a precursor whose aqueous solution was mixed with 10 wt% polyvinyl alcohol (PVA) aqueous solution, hydrolyzed at room temperature, in-situ generated CeO2 nanoparticles, and achieved a nano CeO2- PVA composite coating solution. The CeO2- PVA composite film was obtained by casting the coating solution onto a watch glass at room temperature. The composite coating solution and the film was respectively characterized by TEM, XRD, UV, IR, TG-DTG and PL. The thin composite film presents slight yellow colour and remains highly transparent even when the CeO2 content reaches 2.0 wt%. The optical bandgap Eg value of the film is 3.55eV, exhibiting excellent ultraviolet absorption ability and blue fluorescence characteristics. It is a highly valuable anti ultraviolet material with potential applications in fluorescent lamps and displays. The characterization results indicate that CeO2 nanoparticles in the composite film are encapsulated by polymer molecular chains and there is interaction between them, which increases the glass transition temperature of the polymer. The incorporation of inorganic particles and the residue of hydrolysis by-products do not put a obvious negative impact on the thermal stability of the composite film.