Spectroscopic characterization of the dehydrogenation of boron hydrides on platinum(111)

Results from the study of the adsorption and dehydrogenation of ortho-carborane (C2Bi0H12) and decaborane (B10H14) are presented in this thesis. The study was done under ultrahigh vacuum (UHV) conditions on Pt(111) with surface sensitive techniques, as well as with density functional theory (DFT) calculations.;The results in this thesis present the first detailed DFT calculations of the carborane and decaborane molecules that lead to the identification of their orientations on the surface. Both molecules are adsorbed molecularly at 85 K in a preferred orientation with the dipole moments parallel to the surface.;The Pt(111) surface catalyzes the release of hydrogen from both molecules at temperatures much lower than their normal decomposition temperatures. Molecularly adsorbed carborane is stable on the surface up to 250 K where a new surface intermediate appears which is stable up to 400 K. This surface intermediate is either a closo-borane anion or the BH species. The thermal degradation occurs in stages for both molecules. The hydrogen desorption is completed by the relatively low temperature of 450 K for decaborane, whereas it is ∼ 750 K for carborane. Even after the thermal degradation is complete, boron remains on the surface up to very high temperatures.