Novel inorganic orange pigments based on BiFeWO₆

Abstract

Bi 1¹x La x FeWO 6 (0 ¯x ¯0.30) samples were synthesized by a co-precipitation method. Their crystal structure, optical properties, and color of the pigments were characterized as novel inorganic orange pigments. In the case of the La 3+ -doped samples, the target phase was obtained almost in a single-phase form. Strong optical absorption was observed below 550 nm in all samples. As a result, the Bi 1¹x La x FeWO 6 (0 ¯x ¯0.30) samples exhibited orange colors, and the most vibrant orange hue was obtained at Bi 0.90 La 0.10 FeWO 6 . Although the yellowness value of the Bi 0.90 La 0.10 FeWO 6 (b* = +37.7) pigment was a little smaller than those of the commercially available orange pigments, the redness value of this pigment (a* = +28.5) was larger. Therefore, this pigment exhibited a reddish orange color as compared with the conventional orange ones. In addition, this pigment was chemically stable. Since the Bi 0.90 La 0.10 FeWO 6 pigment is composed of non-toxic elements, it could be a new environmentally friendly inorganic orange pigment.

Influences of Heat Treatment, Particle Arrangement, and Binder Addition on the Mechanical Robustness of Structurally Colored Coatings Formed with Monodisperse SiO2 Spheres

“…[5][6][7][8][9] Therefore, many efforts have been devoted by researchers to reducing and eliminating the use of heavy metals and to the development of safe and sustainable alternative colorants. [10][11][12][13][14] Among the promising candidates for such alternatives are structurally colored materials. [15][16][17][18] Unlike the selective absorption of light based on the molecular and band structures of dyes and pigments, structural color arises from the modulation of light by visible-wavelength-scale microstructures, making it independent of light absorption and allowing for the production of an abundance of safe, inexpensive materials that have the great advantage of not fading as long as the structure remains intact.…”