Autogenic pressure High surface area Reaction under autogenic pressure at elevated temperatures Surface area Thin layers Wavelength regions Magnesium Sand Silicon oxides Silica
Issue Date:
2009
Publisher:
Journal of Physical Chemistry C
Citation:
Volume: 113, Issue: 24, Page : 10521-10526
Abstract:
We report on a reaction to convert St??ber silica or Mediterranean sand to high surface area silicon
(HSAS). The starting silica and/or the sand are reduced by magnesium under the autogenic pressure of the
reactants at 750 ?C for 5 h. After the MgO is removed, HSAS is formed. The surface areas are 200 and 86 m
2/g for the product obtained from the St??ber silica and sand, respectively. The morphology of the final
product is almost identical to that of the precursor silica. The products are stable in air because a thin layer
of SiO2 is present on the surface of the silicon. We have detected luminescence from the HSAS in the
wavelength region of 626-640 nm. ?? 2009 American Chemical Society.
