Preparation of Cobalt Ferrite Thin Films by an Organic-Free, Aqueous Solution-Based Sol-Gel Method

Abstract

Co_xFe_3-xO₄ thin films have been prepared on glass substrates by a new aqueous solution-based sol-gel method without involving any organic additives or solvents. This process consists of (1) deposition of precursor (α-FeOOH) thin films in an aqueous solution, (2) adsorption of Co²⁺ on the precursor film and (3) heat-treatment of the Co-bearing precursor film at 673 K in a flow of 55%CO+45%CO₂. The value of x in the resultant thin films fell around 0.73. The crystalline phases, microstructure, thickness, and magnetization behavior were characterized on the cobalt ferrite films.