Fabrication of silica-supported ZrO2 mesoporous fibers with high thermal stability by sol–gel method through a controlled hydrolysis–condensation process

Silica-supported ZrO2 mesoporous fibers with high thermal stability and fine-tuning mesostructure were successfully fabricated by sol–gel method. Triblock co-polymer of Pluronic P-123 was used as the structure-directing agent. The self-induced acid environment of ZrOCl2·8H2O in ethanol solution was utilized so as to avoid a rapid hydrolysis process and obtain viscous sol precursors for spinning fibers. Meanwhile, the different amounts of KAc were added to adjust such acid environment and control the hydrolysis–condensation process. Silica content of up to 50 mol% was incorporated into the mesoporous zirconia-based framework, providing materials with high surface areas, uniform pore sizes, and pore ordering. The micellization of Zr species dominate the self-assembly process, while the competitive hydrolysis–condensation process between Zr and Si species determined the final mesostructure properties. The obtained fibers were characterized by XRD, FTIR, TG-DTA, UV–Vis diffuse reflectance spectra (UV–Vis DRS), N2 adsorption, SEM and HRTEM measurements.