Sensing of nanostructured CdS thin films via several solution concentrations

Using chemical bath deposition (CBD) methods and various molarities, nanostructured CdS thin films were developed. XRD assured that these films were cubic polycrystalline, containing larger grains as the solution's concentration of cadmium ions increased. Dislocation density values dropped from 79.32 to 62.90 as a result, nevertheless. Also, the strain is lowered from 30.88 to 27.50. AFM results demonstrate that these films suffer a decrease in the value of average particle size, root mean square, and roughness with the molarity concentration. SEM images show CdS thin films at various molarities (0.10, 0.15, 0.20) M, indicating reduced grain size with increased concentration. The optical characteristics indicate a large band gap decreases from 2.46 eV to 2.34 eV and a high transmittance in the visible portion of the spectrum of more than 97.5%. The Refractive Index value changed from 3.23 to 3.11 as the content of cadmium ions increased. CdS films show p-type behavior, reducing resistance with NO2 gas, influenced by molar concentration. The sensitivity of CdS films to NO2 shows a decrement with increased molar concentrations.