Formation of Chemically Complex Intergranular Glass Film: An Effective Strategy to Hinder Grain Coarsening.

Thermally driven grain coarsening is a commonly encountered issue in nanocrystalline ceramics, particularly in high‐temperature environments. The intergranular glass film (IGF) constitutes a crucial component of most ceramics and plays a pivotal role in the process of grain coarsening. In this study, it is proposed to impede grain coarsening by constructing a chemically complex IGF comprising multiple dopants with distinct ionic radii. Ternary dopants encompassing Al3+, Y3+, and La3+ ions are simultaneously incorporated into a ZrO2–SiO2 nanocomposite. To fabricate the nanocomposite, an amorphous precursor powder with uniformly dispersed dopants is prepared using a chemical coprecipitation method, followed by rapid hot pressing to obtain a dense bulk sample. The distribution behavior of ternary dopants at IGFs between adjacent ZrO2 nanocrystallites (NCs) is carefully examined. It is revealed that the ternary dopants coexist at the IGFs. Moreover, Si4+ ions exhibit preferential enrichment at the IGFs. Remarkably, the presence of chemically complex IGFs significantly enhances the resistance to grain coarsening in ZrO2 NCs up to 1000 °C. In these findings, valuable insights are offered for designing and fabricating nanocomposites with exceptional resistance against grain coarsening. [ABSTRACT FROM AUTHOR]