Dy and Eu activated Ca3B2O6 phosphors for near ultraviolet‐based light‐emitting diodes

Abstract

AbstractThe Dy‐ and Eu‐activated Ca3B2O6 phosphors were synthesized by a high‐temperature solid‐state reaction technique and their structural and luminescent properties were investigated. The phosphors are characterized by X‐ray diffraction, photoluminescence spectra, and Commission International de I'Eclairage (CIE) chromaticity coordinates. It is found that the charge compensator Na+ plays an important role in modifying the emission spectral profiles of Dy and Eu ions in the phosphors. The ratio of the emission located at the yellow wavelength portion to that located at the blue wavelength region of the Dy3+ ions can be apparently tuned by changing the Na+ content. The luminescence intensity of the phosphors can be enhanced with introducing Na+ ions as well. The emission colors of Dy/Eu codoped phosphors change from blue to white and successfully acquire the superior white light emission (x = 0.330, y = 0.329) by appropriately tuning the Na+/Dy3+ content and the excitation wavelength. The energy transfer process from Eu2+ to Dy3+ and Eu3+ occurs in the Dy/Eu codoped phosphors, providing a further approach to modify the emission spectral profile of the examined phosphors. The phosphors presented here have promising applications in the fields of light‐emitting diodes.