**4. Conclusion**

Cadmium oxide thin films have been deposited by perfume atomizer spray pyrolysis technique on glass substrate at different solution volume. In this study, the effect of volume of solution on structure, morphology and optical properties of prepared CdO thin film were reported. X-Ray diffraction studies shows that the preferred growth orientation along (111) plane with cubic crystal structure for all solution volume. It is evident that the microstructural parameters vary with volume of solution and may be useful to enhance the properties of CdO thin film for various applications. An average optical transmittance about 55% in the wavelength range 480–800 nm, was obtained. The Tauc graphs were plotted and revealed that the band gap of the CdO thin films can be altered by changing the appropriate solution volume. Intense PL emission peaks were observed at different wavelengths confirms that the presence of oxygen vacancies, defect centre and recombination of electron hole.
