Optical and electrochemical characteristics of sol–gel deposited iron oxide films

Abstract

Homogenous, crack free iron oxide films are prepared by the sol–gel spin coating technique from a solution of iron iso-propoxide and isopropanol. The films were characterized by X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), UV-visible (UV–Vis) spectroscopy and cyclic voltammetry (CV). XRD of the films showed that they had an amorphous structure. The optical constants refractive index ( n) and extinction coefficient ( k) were measured by scanning spectrometer in the wavelength range of 390–990 nm. The n and k values were found n =2.3±0.01 and k =0.2±0.002 at 650 nm. The electrochemical behavior investigated in 0.5 M LiClO 4 propylene carbonate (PC) electrolyte-CV examinations showed good rechargeability of the Li +/e − insertion extraction process beyond 300 cycles. Spectroelectrochemistry showed that these films exhibit weak cathodic coloration in the spectral range of 350–800 nm.