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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Mixed nanostructured thin films composed of In2O3 – AgxO, were synthesized on glass and porous silicon to produce NH3-gas sensor. The films’ structure of the sensor was analyzed by XRD and AFM. The results obtained that polycrystalline nanostructure thin films were prepared. The optical properties indicate that the transmission and the energy gap were decreased with the increase in AgxO ratio. The sensor conductivity changed from n-type for In2O3 up to 10 Vol% AgxO to p-type with mixed oxides. The synthesis gas sensor gives sensitivity toward 40 ppm NH3 gas at different temperatures (50, 100, 150 and 200) ˚C. The maximum sensitivity of mixed films on porous silicon for 15% AgxO ratio is 94.13% with a response time of 11.85 s and a recovery time of 20 s. Porous silicon improves the sensitivity of the prepared sensor by a factor of two with respect to the sensor over the glass. The good sensor properties of In2O3 – AgxO nanostructure mixed oxide at a low temperature indicated as highly efficient NH3 gas sensor.