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Hollow CuO-CeO_2-ZrO_2 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(H_2-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.
Hollow CuO-CeO_2-ZrO_2 nano-particles were prepared with supercritical anti-solvent apparatus by using methanol as solvent and supercritical carbon dioxide as anti-solvent. Two key factors (ie, pressure and temperature) were investigated to explore the effects of catalyst structure and physic-chemical properties (ie, 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 (H 2 -TPR) and oxygen storage capacity (OSC) measurement, respectively. The experimental results showed that lower temperature promoted production of hollow structure nano-particulates. The particle morphology also changed significantly, ie the solid construction was first transferred to hollow structure then back to solid construction. The optimal conditions for obtaining hollow nano-particle s were determined at 45 ° C, 18.0-24.0 MPa.