New observation on the luminescence of CdS clusters in zeolite- Y

Abstract

The excitation spectrum of CdS clusters in zeolite- Y is consistent with their absorption spectrum, both showing two absorption bands that are assigned to the 1 s−1 s and 1 s−1 p transitions, respectively. A new emission at 400 nm is considered to be the recombination of the bounded excitons. The emission firstly increases then decreases with increasing cluster size or loading. The emission by excitation into the 1 s−1 s band is stronger and sharper than that by excitation into the 1 s−1 p band. This phenomenon is attributed to the size inhomogeneity and the strong electron-phonon interaction of the clusters.