PHOTOLUMINESCENCE STUDY OF ZnO NANOPARTICLES PREPARED BY SOL-GEL, REVERSE MICELLE AND LASER VAPORIZATION TECHNIQUES

摘要

ZnO nanoparticles have been prepared by sol-gel, reverse micelle and laser vaporization techniques. All particles have the bulk crystal structure and show quantum size effects in absorption and emission. The particles produced by the sol-gel method are the smallest (4 nm diameter), but all show bandgap shifts and size-dependent dispersed and time-resolved emission spectra. They show emissions that consist of a blue bandgap feature with a sub-nanosecond lifetime and a green feature with multiexponential lifetime decays. Emission from the stearate coated particles produced by the reverse micelle method is particularly intense. The reverse micelle and sol-gel samples in water exhibit signifcant reduction in the intensity of the green emission due to possible modifications of nanoparticle surfaces.