Springs, rings, and spirals of rutile-structured tin oxide nanobelts.

Single-crystalline springs, rings, and spirals have been discovered for the first time in rutile-structured SnO2. The formation process is proposed for minimizing the electrostatic energy due to the polar charges on the (011) surfaces. These structures are not only ideal systems for fundamental understanding of the polarization effect on the morphology at the nanoscale level but also have potential applications as nanoscale sensors, resonators, and transducers.