The effects of addition of a series of organoamine molecules on the lu
minescence of porous silicon has been examined by steady-state photolu
minescence (PL) and Fourier transform infrared spectroscopies. These s
amples, prepared nonanodically via stain etching techniques and charac
terized by atomic force microscopy, show dramatic quenching of visible
PL upon addition of dilute solutions of the above Lewis base adsorbat
es. The fractional changes in integrated PL intensity as a function of
quencher concentration obey a simple equilibrium model, demonstrating
Langmuir-type behavior from which equilibrium constants can be calcul
ated. An observation concomitant with this loss of PL is a diminution
of the silicon hydride stretching frequencies near 2100 cm-1.