Structural, optical and antibacterial response of CaO nanoparticles synthesized via direct precipitation technique

Abstract

Calcium oxide (CaO) is a promising material that works as a glass constituent, catalyst, toxic-waste remediation, poisonous gas absorbent, industrial refectory element for metal smelting, paper bleaching, sulfur neutralization in sugar, cosmetics and drug delivery mediator. This work proposes the synthesis of CaO nanoparticles by direct precipitation technique using an aqueous solution of calcium chloride and sodium hydroxide precursors. The synthesized nanoparticles are characterized for the structure, morphology, chemical composition and optical behavior using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), field effect scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy(EDS), and diffuse reflectance spectroscopy. The XRD results show that the CaO nanoparticles have been synthesized in a cubic crystalline structurewith the average crystallite size of about 13 nm and display aggregated morphology of nanoclusters. The presence of distinct peaks in the FTIR and EDS spectra reveal that the nanoparticles are successfully formed from the chemical recipe of the precipitation process. The optical bandgap has been estimated from the Kubelka-Munk plot and found to be 3.48 eV. The antibacterial activity of CaO nanoparticles has been tested by the well diffusion technique and observed that it shows good antibacterial action against the gram-negative bacterial strains.