Synthesis and characterization of nanocomposite films with a titania glassmatrix by the sol-gel route

Films of thickness similar to 3 mu m containing nanosized metal particles o f iron, nickel and copper respectively were grown on a Coming glass slide u sing a sol-gel technique. The particle sizes had values in the range 6.8 to 20.1 nm. Optical absorption characteristics of different specimens were st udied over the wavelength range 230 to 830 nm. An absorption maximum was ob served at wavelength varying from 270 to 300 nm depending on the nanocompos ite system. The data were analysed on the basis of effective medium theorie s viz., Maxwell-Garnett (MG) and Bruggemann (BR) models respectively. MG mo del showed better agreement with experimental results than BR theory. The v olume fraction as estimated from the least square fitting procedure was fou nd to be in the range 2 to 3%. Copyright (C) 1999 John Wiley & Sons, Ltd.