Hematite is the fourth element in abundance in Earth and most stable allotropic phase of iron. In the recent years intensive investigation has been done due hematite potential application as photoanode in photoelectrochemical cells (PEC) for the hydrogen generation through the water molecule splitting reaction assisted by sunlight. Despite innumerous progresses to make hematite as a commercial material for PEC application, many challenges still need to be overcome. In this sense, undoped and doped (Sn, W, and Ti) hematite will be synthesized by aqueous solution route under hydrothermal conditions at low temperature (at 100 oC) and short time (1 h). For obtaining the desired phase and activate the sample surface, additional thermal treatment at 750 oC is needed. Since it is a consensus that the use of additional thermal treatment at high temperature is mandatory for reaching a good photoelectrocatalytic performance from hematite a truly understanding of temperature effect is still a challenge. The main focus of this research proposal is to investigate and understand the role of temperature of thermal treatment on hematite surface activation using calorimetric methods at (room temperature or high temperature). In addition, the use of dopants and different crystal face will also be investigated to elucidate their effect on charge transport and chemical reactions at the surface. Several techniques will be additionally carried out in combination with water adsorption microcalorimetry such as, X-ray diffraction, High temperature oxide melt drop solution calorimetry and thermogravimetric technique, scanning and transmission electron microscopy coupled with chemical analysis to elucidate the sample composition. These findings will provide a deeper understanding of the fundamental characteristics and limitations of hematite to help us making it suitable materials for application as photoanode in PEC devices.
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