Executive Summary : | This project is motivated by the urgency of basic research necessary to develop environment friendly alternative source of renewable energy namely green hydrogen. The use of solar energy to produce green hydrogen though photocatalytic water splitting has emerged as one of the viable technologies in recent years. There is tremendous activity worldwide to understand how H2O interacts with different solid surfaces that could lead to production of hydrogen. The basic process of water splitting is apparently quite simple where photoexcitation in a semiconductor results in generation of electrons and holes in the conduction and valence bands, respectively. subsequently, these electrons and holes reduce and oxidize water into hydrogen and oxygen, respectively. Thus, the three steps involved are photoexcitation, charge separation and the reaction at the surface of the photocatalyst. Thus, obviously, the electronic band structure of the photocatalyst plays a crucial role. Earth abundant chalcogenide semiconductors have recently received extensive attention as photocatalysts since these can absorb the visible light because of their lower band gap. Interaction of water with oriented single crystals of chalcogenide semiconductor photocatalysts such as Mos2, Ws2, Bi2Te3, and RTe3 with controlled and well characterized surface modifications will provide interesting information about the efficiency of hydrogen production. A mass spectrometer will be used to detect evolution of hydrogen in the vacuum chamber where in-situ techniques such as x-ray photoelectron spectroscopy (XPs), will provide the understanding in terms of the behavior of the electron states. |