Papers by Author: A. Opalińska

Abstract: Nanoparticles of the wide band gap oxides doped with rare earth (RE) ions are prospective materials for application in optoelectronics as phosphors in a new generation of light sources. In this paper the mechanisms of the excitation of efficient 4f-4f intra-shell transitions in RE doped nanoparticles are discussed. These mechanisms either enhance the rate of host to impurity energy transfer or stimulate the intra-shell transitions of RE ions.

Abstract: This paper presents the results of studies on ZrO2 containing 10% Eu3+ as a nanofiller in polyurethane nanocomposites with luminescent properties. The nanocomposites, which are potential materials for electro-optical-electronic applications, were prepared by in-situ polymerization. Emission spectra, thermodegradation, thermal analysis and mechanical properties of polyurethane ZrO2/10% Eu3+ were investigated and the structure examined using HRSEM. The aim was to investigate the influence of the distribution of nanofillers in the composite and the structure of hard domains of polyurethanes on the relevant properties for opto-electronic applications.

Abstract: The luminescence of nanocrystalline tetragonal and cubic ZrO2 has been investigated. The tetragonal undoped ZrO2 revealed two luminescence bands, at ~2.0 eV and 2.7 eV , but only one band at ~2.7 eV was observed from cubic ZrO2. This luminescence was shown to be intrinsic. The regular zirconium-oxygen complex excited state is suggested as being responsible for intrinsic luminescence.