Synthesis and investigation of the effect of precursor on hematite morphology using chemical vapor deposition layer for photoelectrochemical applications

Photocatalytic water splitting technology is one of the new methods that has a high potential for hydrogen production. In this research, chemical vapor deposition method was used for the synthesis of hematite on FTO substrate as a photoelectrochemical cell photoanode. To determine the structure of the synthesized iron oxide and study the morphology of the synthesized structures, X-ray diffraction spectroscopy, scanning electron microscopy and X-ray energy diffraction spectroscopy were used, which well confirmed the synthesis of hematite on FTO substrate. In the hematite synthesis step, it was found that the prewash steps, the presence of TEOS and its amount in the uniformity and thickness of the layer and the type of precursor used in the structure and morphology of the synthesized hematite have a significant effect. Using ferrocene, pyramidal structures of hematite with optimal thickness in the amount of 2 ml TEOS were obtained and for pentacarbonyl iron, cauliflower structures were obtained in the optimal ratio of pentacarbonyl iron (1 ml) / TEOS (0.5 ml) 2: 1. The results of photoanode efficiency of synthesized hematite on FTO substrate showed that the thickness and morphology of hematite have a special role in the photon flux and the maximum photon flux was obtained 1.42 mA/cm2 for the synthesized hematite cauliflower structure.