Effect of Divalent Metal Ions on Thermal Evolution and Band Gap Energy of Cadmium Oxide (CdO) Nanocrystallites: Comparetive Study

In this study, pure and divalent metal ions doped cadmium oxide samples are synthesized by cost effective co-precipitation method at the nanoscale dimensions. Here, we have represented a comprehensive study which conclude that how structural and optical behavior of undoped cadmium oxide has been modified with single doping of Cu, Mn and their co-doping (Cu-Mn) also. The prepared nanopowder is being investigated using different complementary techniques like TG-DTA and UV-Vis spectroscopy to explore their bandgap energy and thermal behavior. A strong and broad optical absorption band is obtained at 262, 250, (312 and 475), (250-350) nm for respectively samples. The optical band gap values are calculated using Tauc’s plot as 4.45, 3.86, 2.39 and 2.44 eV for undoped CdO, Cu doped CdO, Mn doped CdO and Cu-Mn co-doped CdO respectively. UV-Vis spectra revealed that the prepared samples are having high absorbance and extended sufficiently into visible region. Therefore, it is suggested that the co-doping efficiently alter the band gap of the CdO and make it suitable for optoelectronics and other applications like gas sensing, photo catalyst etc.