EFFECT OF THE AMOUNT OF REACTANT ON THE PHOTON-FLUENCE DEPENDENCE IN LASER-INDUCED TRANSIENT FORMATION AT THE SURFACE OF COLLOIDAL SEMICONDUCTOR PARTICLES

A kinetics model was described for the surface electron transfer at il luminated colloidal semiconductor particles to discuss the effect of t he acceptor concentration. The principle is a modification of the reco mbination model which was previously proposed by the authors to unders tand the dependence of the electron-transfer quantum yield on the phot on fluence. The modified recombination model was successfully applied to the experimental results, where the quantum yields for the electron transfer from colloidal CdS to methylviologen were obtained at variou s fluences as a function of acceptor concentration. The new model reve als that the Langmuir-type relationship between the reaction yield and the reactant concentration is not applicable at higher photon fluence s.