Synthesis of Sn doped CuO nanotubes from core-shell Cu/SnO2 nanowires by the Kirkendall effect

Sn doped CuO nanotubes were synthesized by thermal oxidization of Cu/SnO2 core-shell nanowires in air through the Kirkendall effect. The Cu/SnO2 core-shell nanowires were sequentially electrodeposited by forming a SnO2 shell followed by electrodeposition of the Cu core. After thermal treatment in air, the core-shell Cu/SnO2 (13 ± 2 nm thick shell on 128 ± 15 nm in diameter core) nanowires were oxidized to form Sn doped CuO nanotubes with an average wall thickness and outer diameter of 54 nm and 176 nm, respectively. Room temperature I-V characterization indicated that the electrical resistivity of the nanostructures was 870 ± 85 Ω cm. The methodology that was demonstrated is very general and could be used to synthesize coaxial SnO2 shells with a variety of electrodeposited cores. In addition, doped metal oxide nanotubes can be readily synthesized by thermal oxidization of core-shell nanowires in air where the dopant content can be tuned by controlling the shell thickness through adjusting the deposition time.