Development of environmentally friendly inorganic fluorescent pigments, A(3)V(5)O(14) (A = K and Rb) and Cs2V4O11: Crystal structure, optical and color properties

Abstract

To develop the bright-vivid red- and yellow-inorganic fluorescent pigments with high luminescence properties, A(3)V(5)O(14) (A = K and Rb) and Cs2V4O11, inorganic pigments were synthesized by a water assisted solid state reaction (WASSR) method and a conventional solid state reaction method. Although impurity peaks corresponding to the AVO(3) and AV(3)O(8) (A = K, Rb, and Cs) were observed in all samples prepared, the trigonal structure A(3)V(5)O(14) (A = K and Rb) and orthorhombic structure Cs2V4O11 were successfully obtained as a main phase. These inorganic pigments showed the broad absorption band (under 550 nm) originated from CT transitions of VO4 polyhedron, and the strong broad red- and green-emission bands due to T-3(2) -> (1)A(1), and T-3(1) -> (1)A(1), transitions of the [VO4](3-) group. The A(3)V(3)O(14) (A = K and Rb) and Cs2V4O11 pigments showed a bright-vivid red- and yellow-body color, where the a* values of the A(3)V(3)O(14) (A = K and Rb) were +35.5 and +45.9, respectively, and b* value of Cs2V4O11 pigments was +50.3. The L* values of the A(3)V(3)O(14) (A =K and Rb) and Cs2V4O11, inorganic pigments were over +45. These results indicate that the A(3)V(5)O(14) (A = K and Rb) and Cs2V4O11 inorganic pigments could be an attractive candidate as a bright-vivid red- and yellow inorganic pigments.