Preparation and Characterization of Thin Films Bismuth(III) Oxide/Zinc Oxide Nanostructures Prepared by Thermal Evaporation Technique as Gas Sensor Applications

In This work, they made Bismuth oxide (Bi2O3-based) and zinc oxide (ZnO)–doped thin films using thermal evaporation. XRD confirms the phase geometries of monoclinic and (Bi2O3/ZnO) thin films. When ZnO is added, the average crystal size decreases from 17.35 to 8.67 nm. Structures have been examined using Fourier transform infrared (FT-IR) and scanning electron microscopy. The Fourier transform infrared (FT-IR) investigation found no chemical reactions in the (Bi2O3/ZnO) thin films. A scanning electron microscopy (SEM) examination of the (Bi2O3/ZnO) thin films showed uniform results. Increased ZnO doping reduces the diameter by 67.6%, from 34.20 to 11.06 nm. The optical properties of the (Bi2O3/ZnO) thin film material are examined in this work. It has been shown that (Bi2O3/ZnO) concentration increases absorbance and absorption coefficients. The transmittance and energy band gaps decreased as ZnO concentrations with significant UV light absorption increased. The direct current (D.C) electrical conductivity of (Bi2O3/ZnO) thin films is positively correlated with (ZnO) nanoparticle concentration and temperature, according to experiments. At the same time, the activation energy falls with (ZnO) nanoparticle concentration, given a fixed quantity. The gas sensor showed 96.4% sensitivity to H2S gas at 200 °C. The experiment employed 50 ppm H2S. Finally, the (Bi2O3/ZnO) thin film examination reveals their structural characteristics and conductivity. These results may be helpful in UV sensors and gas sensors. The utilisation of (Bi2O3/ZnO) thin film gas sensor has demonstrated significant potential as a viable option for gas sensing systems, primarily attributed to the enhanced surface area achieved by the application of metal oxide catalysts. The present study also discusses the mechanisms implicated in the augmentation of gas response and the broadened range of applications.