Cganging of optical and structural properties of nano layer zinc oxide doping with manganese with physical parametres.

Pure and Mn-doped ZnO nano films were prepared onto glass substrates using the sol - gel method, and optical properties of pure and ZnO:Mn were investigated with regard to different thickness, different annealing temperature and effects of layers. According to our results, increasing the thickness and annealing temperature decrease the measured transmittance spectrum. XRD spectrum shows the crystal structures are formed at high annealing temperature. The band gap energy of nano-films decreases with increasing the annealing temperature (3.45 eV-3.84 eV) and thickness of the nano films (3.38 eV-3.41 eV). This increase is due to improvement of the crystal quality owing to the increase of annealing and thickness of the nano films. Influence of four different solvents that used in the samples, also was investigated. The results of calculating band gap show that the prepared sample by methanol has the highest energy gap and the smallest grain size. This solvent has also the highest transmittance. Samples prepared by ethanol and 1-butanol have the most penetration depth. Gas sensing performance of ZnO depends on the grain size, so using methanol on ZnO can be used in the gas sensor devices for more precise result.