Reversible Quenching of Red Photoluminescence of Porous Silicon with Adsorption of Alcohol OH-Groups I

Abstract

Red (ca. 1.82eV) photoluminescence (PL) of porous silicon was quenched reversibly in accordance with adsorption and desorption of alcoholic OH groups. The alcoholic OH groups adsorbed on SiH_x of porous silicon with hydrogen bonding. From plots of log (PL₁₀₀−PL_T)/PL₁₀₀ vs. 1/T, where PL₁₀₀ and PL_T are the PL intensities at 100 and TK, respectively, the activation energy of ca. 50eV was calculated for the non-radiative deactivation path of the excited electrons which are in an energy state possible to emit red PL. For the nonradiative deactivation path that were made with the adsorption of alcoholic OH groups, the activation energy was assumed to be negligible and independent on temperature.