Synthesis of Bi2Se3 thermoelectric nanosheets and nanotubes through hydrothermal co-reduction method

Bi{sub 2}Se{sub 3} nanosheets and nanotubes were prepared by a hydrothermal co-reduction method at 150, 180, 200, and 210{sup o}C. Bi{sub 2}Se{sub 3} nanosheets, nanobelts and nanotubes were obtained. The Bi{sub 2}Se{sub 3} nanoflakes are 50-500nm in width and 2-5nm in thickness. The Bi{sub 2}Se{sub 3} nanotubes are 5-10nm in diameter, 80-120nm in length, and 1.3nm in wall thickness. X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, and electron diffraction were employed to characterize the products. Experimental results showed that the nanosheets and the nanotubes are hexagonal in structure with a=4.1354A and c=27.4615A. A possible formation and crystal growth mechanism of Bi{sub 2}Se{sub 3} nanostructures is proposed.