Preparation of ternary rare earth sulfide LaxCe2–xS3 as red pigment

In order to investigate the suitability of ternary rare earth sulfide LaxCe2–xS3 in plastic application as a red pigment, we prepared LaxCe2–xS3 via the sulfurization of the oxide powders using CS2 gas. In the sulfurization of LaxCe2–xS3, β-phase and γ-phase ternary rare earth sulfide LaxCe2–xS3 were synthesized at the sulfurization temperature of 1000 and 1250 °C for 3 h, respectively. The UV-vis absorption spectra of synthesized LaxCe2–xS3 showed that the absorption wavelengths of β-phase and γ-phase LaxCe2–xS3 samples were in the region of 617–670 nm and 607–653 nm, respectively. They were in red absorption region. Furthermore, the scanning electron microscopy (SEM) results of the synthesized LaxCe2–xS3 samples were investigated. The typical SEM micrographs indicated that the particle sizes of synthesized LaxCe2–xS3 were in the range of 0.5–6 μm.