Co9S8 nanotubes: facile synthesis and application in the catalytic reduction of 4-nitrophenol

Co9S8 nanotubes have been successfully synthesized via a facile two-step solvothermal method without the assistance of any template or surfactant, using cobalt sulphate (CoSO(4)ai...7H(2)O), urea and sodium sulphide (Na(2)Sai...9H(2)O) as starting reactants, and deionized water and glycol as the reactive medium. The phase and the morphology of the as-obtained product were characterized by means of powder X-ray diffraction, energy dispersive spectrometry and scanning electron microscopy. The result displays that the Co9S8 nanotubes have hexagonal cross-sections, the diameter of the nanotubes is about 200 nm and the wall thickness is of 50 nm. The experiments showed that the Co9S8 nanotubes could be used as new-type catalysts for the reduction of 4-nitrophenol. It was found that the as-obtained Co9S8 nanotubes contributed to the best catalytic activity.