[en] β-PbO₂ 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 PbO₂ nanobelts are enclosed by top surfaces ±(201) and side surfaces ±(101(bar sign)) and their growth direction is [010]. Each PbO₂ 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 PbO₂ nanobelts results in the phase transformation from PbO₂ to PbO and finally to Pb