| ABSTRACT |
Petroleum as an energy source is unsavory because it tied to global warming, the fact that a large percentage of it are sourced from countries with unstable geopolitics, and because it is a finite resource, it will reach a point in time, peak oil; when the production of oil starts to fall and cannot meet the world¿s growing energy consumption. One of the best, reliable alternative energy sources is solar energy. Solar energy can be captured through electrolysis of water and stored in the form of hydrogen which can be kept and used at a later time. A low cost but effective photo-anode will have positive implications in nudging ourselves away from conventional energy generation and towards a hydrogen economy. Hematite ^5;-Fe203 is a potential photo-anode material in terms of band gap, chemical stability in aqueous environment, availability, and relatively low cost. However, hematite is not perfect because it suffers from its extremely short hole diffusion length (about 2nm). Optimization will be done by nano-structuring the hematite to have a higher exposed surface area so that more photo-generated holes are produced near the semiconductor liquid junction. The hematite will be deposited on top of a silicon suboxide layer via spray pyrolysis to encourage Franck van-der Merve growth; after being doped with tin to increase charge carrier density. The hematite will also be encapsulated in a layer of silica prior to annealing to minimize increase in feature size.
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