Preparation, structural and optical characterization of cobalt oxide and cobalt hydroxide nanostructures

Shokrani-Havigh, Roya and Azizian-Kalandaragh, Yashar and Tavana, Ali (2015) Preparation, structural and optical characterization of cobalt oxide and cobalt hydroxide nanostructures. Masters thesis, University of Mohaghegh Ardabili.

Text (تهیه و مشخصه¬یابی ساختاری و اپتیکی نانوساختار¬های اکسید کبالت و هیدروکسید کبالت) Roya Shokrani-Havigh.pdf Download (368kB)

Abstract

In this thesis, Cobalt hydroxide and cobalt oxide nanoparticles have been prepared in different sizes using ultrasound waves by adding different concentrations of oleic acid as a capping agent. Cobalt oxide and cobalt hydroxide nanoparticles were characterazied using techniques such as thermogravimetric analysis (TGA), Diffrential thermal analysis(DTA), X-ray diffraction (XRD), UV-Vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy(SEM), Vibrating sampele magnetometer (VSM). phase transition temperature from hydroxide to oxidehas been determined using TGA and DTA techniques. The XRD pattern shows formation of pure cobalt oxide and cobalt hydroxide compounds in cubic structure. UV-Vis spectroscopy showed that, by increasing in concentration of capping agent, the absorption edge of the sample dicreace and wavelength shifted to blue regien and then band gap increaced. FT-IR analysis showed, variation of energy bounds and shift in places by increasing the concentration of capping agent.the SEM images shows formation of spherical cobalt hydroxide and cobalt oxide nanoparticles. The magnetic measurements showed, variation of magnetic responsibility of cobalt oxide nanostructures by increasing the concentration of capping agent. Finally catalytic and photocatalytic activity of Co3O4 nanoparticles have been investigated.

Actions (login required)

View Item