Nano-silver oxide thin films with high sensitivity for NH3 gas were deposited on glass substrates by the chemical bath deposition technique. The preparations were made under different values of pH and deposition time at 70ᵒ C, using silver nitrate AgNO3 and triethanolamine. XRD analysis showed that all thin films werepolycrystalline with several peaks of silver oxides such as Ag2O, AgO and Ag3O4, with an average crystallite size that ranged between 31.7 nm and 45.8 nm, depending on the deposition parameters. Atomic force microscope (AFM) technique illustrated that the films were homogenous with different surface roughness and thegrain size ranged between 55.69 nm and 86.23 nm. The UV-Vis spectrophotometer showed that the optical direct energy gap ranged between 1.66 eV to 2.12 eV. The silver oxide thin film gives a high sensitivity of 70.12 for NH3 gas at 75°C operating temperature. This study shows that different types of silver oxides can beprepared by the CBD techniques, with the nanostructure to be used in gas sensors and optoelectronic applications.

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In this study, nanocrystalline thin films of Pb_1-xCd_xS were prepared by the chemical bath deposition technique on glass slides at 333 K. The structural parameters of these films were studied by XRD. The thin films were polycrystalline in nature and doping with Cd brought about shifts in peak position and changes in peak intensity. The surface morphology of the films was characterized by AFM and SEM, and the spherical crystallite size of the films was found to range from 23 nm to 38 nm. The optical, absorption, and transmission properties of the films were further determined by UV-vis spectrophotometry, and the direct optical energy gap was found to range from 2.1 eV to 3.95 eV depending on the amount of Cd doping. Finally, the extinction coefficient, refractive index, and real and imaginary dielectric constants of the films were investigated

A nanostructured heterojunction of CdS/Cd2x(CuIn)1-xS2 with x=0.2 was prepared by chemical spray pyrolysis on ITO/glass substrate at 350 °C. The X-ray diffraction pattern obtained from CdS/Cd2x(CuIn)1-xS2 solar cell confirmed the formation of Cd2x(CuIn)1-xS2 (CCIS), CuInS2, In2S3, and CdS phases, with crystallite size of 16 nm for CCIS and 26 nm for CdS films. The morphology of the film surface was obtained by AFM technique, which produced a greater grain size of 58.3 nm for CdS and 80 nm for CCIS surfaces. Optical absorbance analysis confirmed the composition-controlled electronic transition in the thin film, and the energy band gap was observed to red shift with the increase in the value of x. The electrical properties produced a P-type conductivity of CCIS with two activation energies. I–V characteristic in dark condition produced unsymmetrical heterojunctions, whereas abrupt-type heterojunctions were produced from the C–V curve. The solar energy conversion efficiencies achieved upon illumination of 100 mW/cm2 were 0.35%, 0.5%, 0.9%, and 1.28% for CCIS thicknesses of 610, 800, 910, and 1000 nm, respectively.

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