Bright white-light electroluminescence based on nonradiative energy transfer in Ce- and Eu-doped SrS thin films

Abstract
A bright white-light electroluminescence (EL) is obtained in a thin-film EL device with Ce- and Eu-doped SrS phosphors. The device shows a luminance level of 1500 cd/m2 with 5 kHz drive (500 cd/m2 at 1 kHz). The dominant excitation process of the Eu2+ centers is found to be due to an efficient nonradiative energy transfer from the Ce3+ to the Eu2+ centers.