Improvement in white light emission of Dydoped CaMoOvia Znco-doping.

The research in developing a single ingredient phosphor for white-light emission is progressively increasing. It is well known that theF → H(yellow) andF → H(blue) transitions of Dyions give near-white light emission. The white light emission of Dyions can be enhanced via improving the crystallinity of the host phosphor via co-doping of transition metal ions. In this paper, we report a significant improvement in the white light emission of Dydoped CaMoOby co-doping Znions. The x-ray diffraction pattern confirms the tetragonal phase of pure and doped CaMoOphosphor. The peak broadening and a red-shift in the absorption peak are observed by UV-vis absorption analysis of Zn/Dydoped CaMoO. From Photoluminescence studies, we have observed that in Dydoped CaMoO, the 4% Dydoped CaMoOexhibits maximum emission. The Znions are co-doped to further increase the luminescence intensity of CaMoO:4%Dyand the maximum luminescence is obtained for 0.25% Znconcentration. Two intense emission peaks centered at 484 nm and 574 nm related to transitionsF → HandF → Hof Dyion are observed for Dydoped phosphor. TheF → Htransition is the forced electric dipole transition which is affected by its chemical environment. After Znco-doping, theF → Htransition is affected due to a change in asymmetricity around the Dyions. The 0.25% co-doping of Zngives 34% enhancement in luminescence emission of 4% Dydoped CaMoO. As a result, the CIE coordinates of chromaticity diagram and the color purity of the 0.25% Znco-doped CaMoO:4Dyshow improvement in the overall white light emission. We have shown that with Znco-doping, the non-radiative relaxations are reduced which results in improved white light emission of Dyions.