Lead oxide nanobelts and phase transformation induced by electron beam irradiation

$\mathrm{\beta -}{\mathrm{PbO}}_2$ nanobelts, with a rectangular cross section, a typical length of 10–200 μm, a width of 50–300 nm, and a width-to-thickness ratio of 5–10, have been successfully synthesized by simple elevated evaporation of commercial PbO powders at high temperature. The ${\mathrm{PbO}}_2$ nanobelts are enclosed by top surfaces ±(201) and side surfaces $\text{±(101̄)}$ and their growth direction is [010]. Each ${\mathrm{PbO}}_2$ nanobelt is found to have a large polyhedral Pb tip at one of its ends, suggesting the growth is dominated by a vapor–liquid–solid mechanism. Electron beam irradiation of the ${\mathrm{PbO}}_2$ nanobelts results in the phase transformation from ${\mathrm{PbO}}_2$ to PbO and finally to Pb.