Synthesis of nickel and cobalt sulfide nanoparticles using a low cost sonochemical method

Nickel and cobalt sulfides are promising materials in different cutting-edge research areas like solar cells, supercapacitors, catalysts, and electrode materials. Nickel and cobalt sulfides with various stoichiometries have been synthesized sonochemically from Ni(CH(3)COO)(2) ∙ 4H(2)O, Co(CH(3)COO)(2) ∙ 2H(2)O and different sulfur precursors using a direct immersion ultrasonic probe. The products were characterized by X-ray powder diffraction, transmission electron microscopy (TEM) including EDX analysis, IR and UV–Vis spectroscopy and elemental analysis. Following products have been obtained: NiS, Ni(3)S(4), CoS(1.097) and Co(9)S(8), with average crystallite sizes in the range 7−30 nm. Effects of different reaction conditions on the size, morphology and optical band-gap energy were evaluated. Optical band-gap energies in the range 3.3 eV−3.8 eV were observed for the obtained nanoparticles.