文摘
Hollow CuO-CeO2-ZrO2 nano-particles were prepared with supercritical anti-solvent apparatus by using methanol as solvent and supercritical carbon dioxide as anti-solvent. Two key factors (i.e., pressure and temperature) were investigated to explore the effects of catalyst structure and physic-chemical properties (i.e., morphology, reducing property, oxygen storage capacity and specific surface area). The resulting materials were characterized with X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller (BET), hydrogen temperature programmed reduction (H2-TPR) and oxygen storage capacity (OSC) measurement, respectively. The experimental results showed that lower temperatures promoted production of hollow structure nano-particulates. The particle morphology also changed significantly, i.e. the solid construction was first transferred to hollow structure then back to solid construction. The optimal conditions for obtaining hollow nano-particles were determined at 45 °C, 18.0–24.0 MPa.