Synthesis and optical properties of Mn-doped Ba3Al2O6 intense blue oxides

The solid solution of Ba 3 Al 2- x Mn x O 6+ y (0 ≤  x  ≤ 0.2) is successfully synthesized through solid state reaction. The colors of compounds are tuned from sky blue ( x  ≤ 0.1) to ocean blue ( x  = 0.2) with the increase of Mn content. The X-ray diffraction data shows that the major phase of all the as-synthesized samples is cubic Ba 3 Al 2 O 6 structure with the space group of P 2 1 3. The oxidation state of Mn is confirmed to be +5 by X-ray photoelectron spectroscopy analysis. UV–Vis absorption spectroscopy demonstrates that the sample's color comes from the d - d transition of Mn 5+ located in [AlO 4 ].