BiFeO3 films on steel substrate by the citrate method

We deposited BiFeO3 films on stainless steel substrates using a simple low-temperature wet-chemical route. Bismuth and iron nitrates were used as metal source and citric acid as chelating agent to prepare a water solution and deposit the film by dipping the steel substrate in the viscous solution. We have investigated the composition, crystallinity and structure of the BiFeO3 film on steel by X-ray diffraction, X-ray photoelectron spectroscopy, high resolution scanning electron microscopy, conventional and high resolution transmission electron microscopy, and energy dispersive spectroscopy techniques. The film deposited on the steel substrate has two sublayers: a very thin (about 100 nm) nanocrystalline layer, with crystallite size of few nanometers, and a thicker (below 1 μm) crystalline layer.