Optics and Photonics Society of Iran

sulfur doped molybdenum trioxide (MoO3:S) thin films were deposited on the glass substrate by spray pyrolysis method using an aqueous solutions of ammonium molybdate tetrahydrate and thiourea with sulfur to molybdenum (S :MO) molar ratios equal to 4 and 10 at substrate temperature of 310 ºC. Also, the structural, morphological and optical characterizations of samples were carried out using XRD, field emission scanning electron microscope (FESEM) images and optical spectrum. These results indicate the formation of a MoO3 polycrystalline structure at orthorhombic phase with preferred orientation along (020) plane and MoS2 hexagonal secondary phase. FESEM images showed that a sponge-type structure with cubic particles of nano-metric dimensions. Optical studies showed the MoO3:S layers have a high absorption coefficient in the visible region, and after annealing the band gap values decreased significantly.