Controlled synthesis of ZnO nanowires or nanotubes via sol–gel template process

ZnO nanowires and nanotubes have been rationally fabricated within the nanochannels of porous anodic alumina templates by an improved sol–gel template process. X-ray diffraction and selected area electronic diffraction demonstrate that the as-obtained ZnO nanowires and nanotubes can be indexed to hexagonal wurtzite polycrystalline. In this method, zinc nitrate and urea are used as precursors, zinc nitrate serve as zinc ions source, and urea offered a basic medium through its hydrolysis. ZnO nanowires or ZnO nanotubes can be obtained easily by controlling hydrolysis time. The formation mechanism of ZnO nanowires and nanotubes was also discussed.