Tunable luminescence in Ce3+/ Mn2+ co-doped ZrO2 nanophosphor integrated with theoretical studies on possible (ZrO2)n clusters using DFT method

Abstract

A series of single-phase ZrO2: x (0.02) Ce3+, y (0.01 and 0.03) Mn2+ nanophosphors with tunable luminescence has been prepared by chemical route, i.e. sol-gel method. Singly Ce (0.02) doped ZrO2 phosphor can be efficiently excited by UV light and provides bright blue emission along with host emissions as confirmed by CIE 1931 chromaticity diagram. At Mn2+ concentrations (y = 0.01 and 0.03)), single component ZrO2:xCe3+,yMn2+ nanophosphors with tunable colors have been obtained successfully, and the luminescence intensity quenches, typically due to direct energy transfer to quenching sites (defects and impurity ions). These result conclude that the ZrO2:Ce3+,Mn2+ nanophosphor is a promising candidate for near UV-excited Light emitting diodes (LEDs). The theoretical calculations were performed on the structure, vibrational and electronic properties of (ZrO2)n (n = 2, 3, 4) clusters with DFT method. Especially, we executed the density functional theory (DFT) calculation for calculating the HOMO-LUMO bandgap of supposed clusters (ZrO2)n along with molecular electrostatic potential (MEP) mapping of the clusters.