Effect of sulfur precursor concentration on the structures and optical properties of CdS nanowire array on Cd foil by solvothermal method

Abstract

CdS nanowire array on foil has been fabricated through a solvothermal method, which is uniform, regular and approximately perpendicular to the Cd foil. With the variation of sulfur precursor concentration, the relative intensity of (100), (002) and (101) peak are variable. The nanostructured CdS show the preferential (002)-orientation growth. At the sulfur concentration of 0.1 mol/l, 0.2 mol/l and 0.3 mol/l, CdS nanowires are approximately perpendicular to the Cd foil. At the high sulfur concentration, the characterization of array is destroyed. The band gap, which are estimated from the absorptance spectra using the Kubelka-Munk method, increase with the increasing sulfur precursor concentration until the concentration reaches up to 0.4 mol/l and no longer increases. It is very important to understand the relation between the experimental parameters and the physical properties of the CdS nanowires.