Formation of self-organized platinum nanoparticles and their microphotoluminescence enhancement in the visible light region

Formation of Pt nanoparticles or nanoisland films as a function of annealing temperature, initial thickness, underlying substrates, and annealing process is investigated. Using microphotoluminescence (PL) measurement, we find great enhancement of self-emission in visible spectrum from Pt nanoparticles. The integral intensity of the micro-PL of the 49.38 nm Pt nanoparticles is 38 times of that of the Pt thin film. In addition, the peak wavelength varies from 554 to 615 nm as the surface morphology of Pt changes due to different annealing parameters. Spectral analyses suggest that this enhancement of micro-PL from Pt is due to the local field enhancement mechanism analogous to that of PL from noble metals. (C) 2007 American Institute of Physics.