Research on preparation and reflection properties of (Sm_0.875La_0.125)₂Zr₂O₇

Sm₂Zr₂O₇ is a promising material in the field of thermal barrier coating due to its extremely low thermal conductivity, large thermal expansion coefficient, low sintering rate and good thermal stability. In order to improve the reflective properties of the Sm₂Zr₂O₇, La element was dopted in Sm₂Zr₂O₇. The (Sm_0.875La_0.125)₂Zr₂O₇ with pyrochlore structure was prepared by solid-phase reaction sintering, and the impact of sintering temperature, microstructure and energy band structure on its reflection property were analyzed through X-ray Diffraction (XRD), scanning electron microscope (SEM) and near infrared reflectance spectroscopy (NIRS). The XRD images show that the element La has been successfully adulterated into Sm₂Zr₂O₇ with the pyrochlore structure remaining unchanged, as the particle sizes grow even with the increase of the sintering temperature. The particle distribution was in best uniformity and the band gap is the narrowest, resulting in the highest reflectivity greater than 80% within the 780-2 500 nm wave band. Especially it is over 90% for partial wave bands. To some extent, such good reflectivity has a positive effect in the development of Sm₂Zr₂O₇ surface protection.