Synthesis and Characterization of Hydrothermal Synthesized Ultra-Red CdS_1−xSe_x Pigment

Abstract

Ultra-red pigment is in urgent need to enrich the colour range as well as to improve the quality of ceramic product. In this study, ultra-red CdS_1−xSe_x pigments (CP) were synthesized through hydrothermal technique. The effects of S/Se ratio on the structural and optical properties of CPs were investigated. CPs were characterized by XRD, ICP, SEM and UV-vis techniques. The colorimetric parameters of CPs were measured as also their band-gaps were estimated based on Tauc plot method. Furthermore, detailed formation mechanism of CdS_1−xSe_x has been elucidated. The results demonstrate that different compositions of CdS_1−xSe_x can be facilely obtained by adjusting the R value (starting S/Se molar ratio); when R is equal to 0.67 and 0.83, the prepared samples are CdS_0.75Se_0.25, when R is equal to 1.00, 1.17 and 1.33, the prepared samples are CdS_0.571Se_0.429. It is found that excessive S²⁻ plays critical role in CdS_1−xSe_x formation. CP prepared with R=1.00 owns L*=44.69, a*=49.93, b*=22.66, implying an excellent red colour, which indicates potential use as an ultra-red ceramic pigment.

GRAPHICAL ABSTRACT

Keywords:

• CdS_1−xSe_x
• Ultra-red pigment
• Excessive S²⁻
• Colour performance