EFFECT OF THICKNESS AND ON EFFICIENCY OF IRON OXIDE THIN FILMS PHOTOCATALYTIC DEGRADATION

Abstract

This paper examines the relationship between the thickness of the iron oxide thin layers and their photocatalytic activity in the breakdown of the organic dyes in solar radiation. Pyrolytic decomposition of organometallic precursors, including ferrocene, 4-nitrophenylferrocene and 4-ferrocenylaniline, was used on fluorine-doped tin oxide (FTO) as substrates to form iron oxide thin films. Controlled variation of precursor mass (0.1g and 0.125 g) was used to form films of varying density and morphologies. FTIR, SEM, EDX, and UV/Visible spectroscopy were used to provide structural and morphological characterization and establish the effective creation of uniform films of iron oxide where the creation of grain clusters and the surface coverage vary with the thickness of the film. The photocatalytic ability was determined by the degradation of methylene blue (MB) dye using sunlight. The rate of degradation also improved with optimal film thickness that was at its highest at more than 70 percent of the film produced using 0.125 g ferrocene (S2). To the optimal thickness, further aggregation abolished the number of active sites on the surface and hindered the flow of light, which led to low photocatalytic activity. The results prove that careful regulation of the film thickness is essential in maximizing the ratio between surfaces and volume, charge transfer mechanisms, and the general process of photocatalysis of iron oxide thin films.