White electroluminescence from a prototypical light-emitting diode based on CdS/Si heterojunctions

CdS/Si heterojunctions have been synthesized through growing nanocrystal CdS on the porous polysilicon by using a chemical bath deposition. The prototypical light-emitting diode (LED) based on CdS/Si heterojunctions, which shows an obvious rectification behavior, has been constructed. White electroluminescence (EL) from this prototypical LED can be observed under the forward bias with similar to 4.0 V, which is broad and ascribed to the nanocrystal silicon, the band gap emission and the defect levels emissions of nanocrystal CdS. Through controlling the forward bias, the chromaticity coordinate, correlative color temperature and color rendering index of white EL can be purposefully tuned. The physical properties obtained indicate that this prototypical LED based on CdS/Si heterojunctions ought to be as a potential candidate for the application in the field of white light-emitting diodes. (C) 2017 Elsevier B. V. All rights reserved.