An improved sol-gel template synthetic route to large-scale CeO2 nanowires

Large-scale CeO2 nanowires were prepared successfully by an improved sol-gel process within the nanochannels of porous anodic alumina templates. In this process, cerium nitrate and urea were used as precursors, cerium nitrate acted as cerium ions source, and urea offered a basic medium through its hydrolysis. The as-synthesized CeO2 nanowires can be indexed as a fluorite-structure and the size of nanowires is uniform, with diameters of about 70 nm. The formation mechanism of nanowires is also discussed here. This method is more efficient than a traditional sol-gel template process for small pore diameter templates. (C) 2004 Elsevier Ltd. All rights reserved.