title: Study of porous silicon nanostructures as hydrogen reservoirs.
abstract: The amount of hydrogen present in porous silicon (PS) nanostructures is analyzed in detail. Concentration of atomic hydrogen chemically bound to the specific surface of PS is quantitatively evaluated by means of attenuated total reflection infrared (ATR-IR) spectroscopy and temperature-programmed desorption (TPD) spectroscopy. The concentration values are correlated to the PS nanoscale morphology. In particular, the influence of porosity, silicon nanocrystallite dimension, and shape on hydrogen concentration values is described. Hydrogen concentrations in fresh, aged, as well as in chemically and thermally treated PS layers are measured. Maximal hydrogen concentration of 66 mmol/g is detected in nanoporous layers with high (>95%) porosity consisting of nanocrystallites with dimensions of about 2 nm. Mass energy density that can be potentially obtained from this amount of hydrogen through a low-temperature fuel cell is estimated to be about 2176 W-h/kg and is found to be comparable with other substances containing hydrogen, such as hydride materials and methanol, which are usually used as hydrogen reservoirs.
authors.affiliation: Materials Physics Laboratory, LPM, CNRS UMR-5511, INSA de Lyon, 7 avenue Jean Capelle, Bat. Blaise Pascal, 69621 Villeurbanne Cedex, France. vladimir.lysenko@insa-lyon.fr
authors.forename: Vladimir
authors.initials: V
authors.lastname: Lysenko
authors.forename: Fabrice
authors.initials: F
authors.lastname: Bidault
authors.forename: Sergei
authors.initials: S
authors.lastname: Alekseev
authors.forename: Vladimir
authors.initials: V
authors.lastname: Zaitsev
authors.forename: Daniel
authors.initials: D
authors.lastname: Barbier
authors.forename: Christophe
authors.initials: C
authors.lastname: Turpin
authors.forename: Francesco
authors.initials: F
authors.lastname: Geobaldo
authors.forename: Paola
authors.initials: P
authors.lastname: Rivolo
authors.forename: Edoardo
authors.initials: E
authors.lastname: Garrone