Formation of CuS nanotube arrays from CuCl Nanorods through a gas-solid reaction route

Well-aligned CuCl nanorods standing on a Si substrate were prepared via evaporation of CuCl powder in vacuum. Using these CuCl nanorods as a precursor, arrays of CuS nanotubes with diameters in the range 150–250 nm and lengths up to several micrometers have been successfully obtained through a gas-solid sulfurization reaction. Scanning electron microscopy indicates that the morphology and orientation of the parent CuCl nanorods are more or less retained after the CuS nanotube growth. The formation of CuS and the consumption of the CuCl precursor occur at the same time as the gas-solid reaction proceeds, and the nanotube growth pathway can be described in terms of Kirkendall effect.