TiO2-PMMA nanohybrids of enhanced nanocrystallinity

A systematic investigation has been conducted into TiO2-PMMA nanohybrids derived from wet chemistry methods, aimed at understanding the mechanisms responsible for the amorphous TiO2 phase in nanohybrids, which cannot be avoided under the conditions tolerable by PMMA matrix. The largely amorphous TiO2 state is shown to relate to the fast development of stiff Ti-OH networks during hydrolysis and condensation, assisted by the PMMA entrapment. A post-hydrothermal treatment has been successfully devised to enhance TiO2 nanocrystallinity. TiO2 nuclei are shown to involve in the rearrangement of flexible Ti-OH networks, giving rise to the densification of Ti-O-Ti bonds. An appropriate pre-annealing can provide an optimized concentration of TiO2 nuclei, in competition with a strong hindrance effect resulted from the polymerization of PMMA. The functional properties of the TiO2-PMMA nanohybrids have been correlated to their nanostructures, where both linear and nonlinear optical responses are shown to increase with the enhancement of TiO2 nanocrystallinity.

Author dc:creator

• AKHMAD HERMAN YUWONO

• Nanohybrids, TiO2 nanoparticles, Enhanced Nanocrystallinity, Optical Poperties