Synthesis and optical properties of ZrO2 with incorporated Ti nanoparticle/polymer hybrid

Transparent ZrO2 with incorporated Ti nanoparticle/polymer hybrids were synthesized from zirconium methacrylate and titanyl acetylacetonate via hydrolysis and polymerization in 2-methoxymethanol. The formation of the polymer matrix was confirmed by infrared and nuclear magnetic resonance spectroscopies. Transmission electron microscopy and energy-dispersive X-ray analysis revealed that the crystalline ZrO2 with incorporated Ti nanoparticles were well dispersed in the polymer matrix. The absorption edge of a thin film of the undoped ZrO2 nanoparticle/polymer hybrid was blueshifted when compared to that of bulk ZrO2, whereas that of the ZrO2 with incorporated Ti nanoparticle/polymer hybrid exhibited a bathochromic shift of the absorption edge to a wavelength of 310 nm. The refractive indices of the hybrid films formed on Si substrates were dependent on the Ti concentration in the ZrO2 nanoparticles, and increased with an increase in the Ti content. On the other hand, the Abbe number of the ZrO2 with incorporated 20 mol% Ti-based hybrid system was the highest. The thin film of the ZrO2 with incorporated 50 mol% Ti nanoparticle/polymer hybrid had a refractive index of 1.603 at 589 nm.