Preparation of porous SnO2 helical nanotubes and SnO2 sheets

• Synthesized porous SnO2 helical nanotubes with diameters of 100–120 nm.
• Synthesized porous SnO2 sheets template by graphite sheets.
• The tubular and sheet SnO2 have small initial irreversible capacity loss of 3.2 and 2.2%.
• The tubular structure shows better discharge capacity than the sheet structure.

We report a surfactant-free chemical solution route for synthesizing one-dimensional porous SnO2 helical nanotubes templated by helical carbon nanotubes and two-dimensional SnO2 sheets templated by graphite sheets. Transmission electron microscopy, X-ray diffraction, cyclic voltammetry, and galvanostatic discharge–charge analysis are used to characterize the SnO2 samples. The unique nanostructure and morphology make them promising anode materials for lithium-ion batteries. Both the SnO2 with the tubular structure and the sheet structure shows small initial irreversible capacity loss of 3.2% and 2.2%, respectively. The SnO2 helical nanotubes show a specific discharge capacity of above 800 mAh g−1 after 10 charge and discharge cycles, exceeding the theoretical capacity of 781 mAh g−1 for SnO2. The nanotubes remain a specific discharge capacity of 439 mAh g−1 after 30 cycles, which is better than that of SnO2 sheets (323 mAh g−1).