Enhanced photoluminescence in CaMoO4:Eu3+ by Mn2+ co-doping

Abstract

Phosphors doped with rare-earth elements have been extensively employed as white light emitting diodes (wLEDs). Red component is essential in realizing the warm white light efficiently. In this work, we report enhancement in red luminescence of Eu doped phosphor by transition metal doping. Here, a series of Eu3+ doped CaMoO4 and Mn+2/Eu3+ co-doped samples are synthesized successfully by facile auto combustion method. Structural and optical analyses of all samples are studied. UV–Vis analysis of Eu3+ doped CaMoO4 samples ascertains the red-shift in the absorption peak and peak broadening in Mn+2/Eu3+ co-doped CaMoO4. PL study shows an increase in the intensity of emission peaks at 610–630 nm and at 702–711 nm wavelength range up to 4 at % Eu3+ doped CaMoO4, which indicates effective energy transfer from Mo–O charge transfer band to 5D0 level of Eu3+. Luminescence intensity is further increased by Mn+2/Eu3+ co-doping in CaMoO4. For 0.3% at Mn+2 co-doping in CaMoO4:4Eu3+, it is observed that upon 290 nm excitation there is a decrease in the emission broadband around 425 nm–575 nm and increase in intensities of peaks at 612 nm, 615 nm, 654 nm, and 702 nm. Therefore, it is concluded that with proper tuning of Mn+2/Eu3+ doping in CaMoO4, prepared phosphor might have potential application in the fields of lighting and display.