Entropy-stabilized oxides owning fluorite structure: preparation and sintering

Abstract

Entropy-Stabilized Oxides are advanced ceramic materials that possess highly desirable functional properties. Through a five-component oxide formulation, these materials utilize configurational entropy to achieve phase stabilization. In this study we have successfully synthesized a novel type of high-entropy fluorite oxide, specifically Zr0.2Hf0.2Ce0.2Yb0.2Gd0.2O2-δ, through the Self Propagation Room Temperature reaction (SPRT) method. Through heat treatment experiments, it was observed that the phase composition of all samples remained a single phase after high-temperature heating. Furthermore, a thermal treatment at 1500°C resulted in a fully crystallised single-phase fluorite structure. The powders also demonstrated a lack of agglomeration, which allowed for the sintered specimen to exhibit sufficient densification with a small porosity that was uniformly distributed throughout the samples.