Tailoring the Optical Bandgap of Pulse Electrodeposited CoFe2O4 Thin Films.

In this paper, we have focused on the characterization of CoFe₂O₄ thin films grown on FTO substrate by pulsed electrodeposition technique followed by an annealing treatment in air at 500°C during 24 h. The formation of a polycrystalline structures that exhibit cubic spinel phase with an average crystallite size of 45 nm is investigated by XRD and FT-IR studies. SEM observations indicate that the shape of crystallites changes as the number of applied cycles increases. The surface profilometry measurements show that surface roughness of CoFe₂O₄ thin films varies from 116 nm to 229 nm with the number of applied cycles. The optical band gap of the samples was determined to be in the range 1.74–1.98 eV. [ABSTRACT FROM AUTHOR]