Hydrothermal synthesis of CdO nanoparticles for photocatalytic and antimicrobial activities

Abstract

CdO is an II-IV group n-type semiconductor coming under the non stochiometric condition such as interstitial cadmium or oxygen vacancies. CdO nanoparticles having the direct band gap of 2.5 ​eV with an indirect band gap of 1.96 ​eV. CdO nanoparticles were synthesized by using hydrothermal method. The main raw materials used for CdO nanoparticles are cadmium nitrate and ammonium hydroxide. This sample was characterized by XRD, UV-DRS, TEM, FE-SEM with EDS and FTIR. It exhibits simple cubic structure with an average crystallite size of 27 ​nm. The surface morphological image displays spherical like structure with agglomeration. The vibrational stretching mode of Cd–O is 493 ​cm−1. The optical energy bandgap is estimated as 2.56 ​eV. The significant antimicrobial activities were studied against gram negative (Escherichia coli) and gram positive (Staphylococcus aureus) bacteria. The zone of inhibition is found to be more for gram negative than gram positive bacteria. The photocatalytic activity of cationic dye is also studied for hydrothermally prepared CdO nanoparticles.

Keywords

• Crystalline size
• Agglomeration
• Band gap
• Cationic
• Inhibition