CONTROLLED GROWTH OF COPPER NANOPARTICLES AND NANORODS IN THE CHANNELS OF SBA-15 BY SUPERCRITICAL FLUID DEPOSITION

Copper nanoparticles and nanorods were prepared in the one-dimensional channels of SBA-15 supported by a modified supercritical fluid deposition (SCFD) method. In this approach, cheap and widely available copper nitrate, which is insoluble in supercritical CO2 (scCO2), was used as the copper source and ethanol as the co-solvent, thus avoiding the employment of expensive and less available scCO2-soluble precursors. The deposition was carried out at the pressure of 21-25MPa and temperature of 50 degrees C, followed by calcinations at 500 degrees C and H2 reduction at 500 degrees C. The results showed that highly dispersed Cu nanoparticles or nanorods were obtained controllably just by varying the deposition time, as characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). On the other hand, when Cu(acac)2 was used as the precursor and without any co-solvent, only nanoparticles were formed in the channels of SBA-15 no matter how long the deposition time.