Modification of photoacoustic and photoluminescence spectra of manganese-doped nanocrystals of ZnS due to carboxylic acids

摘要

Mn-doped ZnS nanocrystals (ZnS:Mn2+) have been studied from the viewpoint of large luminescence efficiency. Moreover, the photoluminescence (PL) intensity due to Mn2+ ions is enhanced with the modification by carboxylic acids. Because of the scattering effects there have been few investigations on the optical absorption of ZnS:Mn2+ nanocrystals. Photoacoustic (PA) technique is useful for scattering materials and the signal intensity shows a peak (similar to3.2eV) owing to Mn2+ ions absorption. The peak intensities with modification are larger than those without the modification, indicating increase in the role of nonradiative processes. The PL signal intensity shows a peak (similar to2.0eV). The peak intensities with the modification are smaller than that without the modification, indicating the increase of role of nonradiative processes. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 13]