Crystal structure characterization and up-conversion luminescent properties of BaIn2O4 phosphor

Er3+ / Yb3+ doped BaIn2O4 up-conversion (UC) phosphors are synthesized and their UC luminescent properties are characterized. BaIn2O4 has P21/c space group but Rietveld refinement suggests it has twice smaller cell parameter (a = 10.3975 Å, b = 5.8295 Å, c = 14.4457 Å) and volume than previous reported structure. Refinement also reveals Er3+/Yb3+ replaces In3+ ions in lattice because of the existence of InO6 octahedra. In these BaIn2O4 phosphors, co-doping with Yb3+ ions changes the predominant UC emission from green ( 2H11/2, 4S3/2 → 4I15/2 of Er3+) to red (about 665 nm, 4F9/2 → 4I15/2 of Er3+). By controlling of Er3+/Yb3+ concentrations, the BaIn2O4 phosphors have the potential of generating various UC spectra and color tunability. The pumping powers study shows two-photon process in these phosphors.