Selective growth and unveiling semiconductor nanostructured based La,Mo and O elements: Structural, morphological, and optical investigations

Abstract

La2Mo2O9 ternary compound thin film has been prepared by the chemical spray pyrolysis technique on glass substrates at 460°C. Characterization via X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray, X-ray photoelectron spectrometry (XPS) and spectrophotometry through reflectance and transmittance measurements were performed. X-ray analysis shows that La2Mo2O9 material crystallizes in cubic structure belonging to the P 213 space group with a preferred orientation of the crystallites along (210) direction parallel to the substrate plane. Raman spectroscopy witnesses the presence of bonds like La-O and Mo-O. SEM observation shows that the prepared film exhibits a uniform grain of regular sizes in the range of 70–120 nm and some chains. EDX spectroscopy highlights the presence of La, Mo and O elements with a slight non-stoichiometry reflecting the oxygen deficiency. XPS measurements reveal the well defined states O 1s, Mo 3d5/2, Mo 3d3/2, La 3d5/2 and La 3d3/2 of oxygen, molybdenum and lanthanum elements. Optical measurements show a high transparency in the visible range. These measurements were used to deduce the optical band gap and Urbach energy.