Synthesis and properties of novel turquoise-green pigments based on BaAl2-xMnxO4+y

BaAl 2-x Mn x O 4+y (0 ≤ x ≤ 0.10) showing intense turquoise to green colors were prepared by the sol-gel method from metal nitrides as precursors and followed by a thermal treatment at 900 °C. The X-ray diffraction of all of the as-synthesized samples are indexed with BaAl 2 O 4 stuffed tridymite structure. The oxidation state of Mn is confirmed to be +5 by X-ray photoelectron spectroscopy analysis. The colors of the samples are tuned to intense turquoise and green with the increase of Mn content . The optical properties are characterized by UV–Vis absorbance spectra and CIE L ∗ a ∗ b ∗ coordinates. The reason for the intense colors is due to the Mn 5+ doping in the [AlO 4 ] tetrahedral sites. The pigments are applied to poly(methyl methacrylate) (PMMA) and the colours of the polymer composite were characterized.