ABSTRACT The development of next‐generation thermal barrier coating technology urgently requires rare‐earth zirconate materials that combine low thermal conductivity with high thermal expansion coefficients. However, traditional synthesis methods often face challenges such as high energy consumption, the use of toxic chemical reagents, or inadequate control over microstructure. This paper reports an environmentally friendly, low‐cost food additive‐assisted precursor method that successfully achieves the controlled preparation of high‐performance rare‐earth zirconate nanoparticles. Using the food additive fructose as a chelating agent, uniformly grained and well‐dispersed Ln 2 Zr 2 O 7 nanopowders were synthesized. This green synthesis strategy effectively suppresses grain overgrowth, yielding exclusively nanostructured powders. A phase transformation from ordered pyrochlore to defect‐rich fluorite occurs as the cation radius ratio r (Ln 3+ )/ r (Zr 4+ ) decreases. Ceramic bulk materials fabricated from the nanopowders exhibit outstanding thermal conductivity and thermal expansion coefficient. Density functional theory (DFT) calculations determined the material's mechanical parameters, and experiments confirmed that the fluorite phase EZO possesses the highest hardness and compressive strength. Thermophysical testing indicates that the resulting Sm 2 Zr 2 O 7 ceramics exhibit a thermal expansion coefficient as high as 12.16 × 10 −6 K −1 over the temperature range from room temperature to 1200°C, while Gd 2 Zr 2 O 7 has a low thermal conductivity of 1.017 W/(m·K) at 1200°C. This “green synthesis for high‐performance” strategy establishes a new paradigm for large‐scale production of advanced thermal barrier coating materials, demonstrating broad application prospects.
Xu et al. (Thu,) studied this question.