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

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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 Eu 3+ doped CaMoO 4 and Mn +2 /Eu 3+ co-doped samples are synthesized successfully by facile auto combustion method. Structural and optical analyses of all samples are studied. UV–Vis analysis of Eu 3+ doped CaMoO 4 samples ascertains the red-shift in the absorption peak and peak broadening in Mn +2 /Eu 3+ co-doped CaMoO 4 . 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 % Eu 3+ doped CaMoO 4 , which indicates effective energy transfer from Mo–O charge transfer band to 5 D 0 level of Eu 3+ . Luminescence intensity is further increased by Mn +2 /Eu 3+ co-doping in CaMoO 4 . For 0.3% at Mn +2 co-doping in CaMoO 4 :4Eu 3+ , 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 /Eu 3+ doping in CaMoO 4 , prepared phosphor might have potential application in the fields of lighting and display. • Charge transfer between the host (MoO 4 −2 ) levels to the dopant (Eu +3 ) levels. • Shift in the band-gap of CaMoO4 by Eu +3 doping. • Tuning of PL emission of CaMoO 4 : Eu +3 by Mn +2 co-doping. • Increase in the asymmetric parameter (A s ) of PL emission for a 0.3% Mn +2 co-doped CaMoO 4 : 4Eu +3 sample. • Shift in CIE coordinate to redder region by co-doping of 0.3% Mn +2 in CaMoO 4 : 4Eu +3 .