Surface Chemistry of Porous Silicon Surfaces

Ongoing investigations into the chemistry of porous silicon surfaces seek to develop methods for the preparation of chemically functional interfaces that protect the underlying silicon nanocrystallites from degradation without changing or annihilating their intrinsic behavior. The native, hydride-terminated surface is only metastable under ambient conditions and oxidation of freshly prepared porous silicon commences within minutes when exposed to air. While surface oxide can suitably passivate the nanocrystalline silicon and stabilize its photoluminescence, the electrically insulating and structurally defective character of this oxide layer 

Beyond the motivation to fabricate working systems from functionalized porous silicon, there is also more fundamental interest in the reactions of its surfaces. Because the vast surface of nanocrystalline silicon contains a large fraction of the total atoms, the composition and environment of the silicon interface are believed to affect greatly the physical, chemical, and electronic properties of the material. In particular, functionalization of porous silicon with certain organic groups is known to diminish photoluminescence [27] however, the mechanism of quenching has 

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