Electronic structure and surface chemistry of alkyl-passivated Si nanoparticles

We have synthesized the n-butyl-passivated Si nanoparticles with mean diameter of 1.4 nm by the solution routes, and have carried out the various spectroscopic studies in order to investigate their optical properties, electronic structures, and surface chemistry. It is found that photoluminescence (PL) spectra of these Si nanoparticles strongly depend on the surface conditions. Moreover, it is found their electronic features obtained from the synchrotron-radiation valence-band photoemission and PL spectra are reproduced by the recent quantum Monte Carlo calculation. From the synchrotron-radiation Si 2p core-level photoemission spectra, it is found that their interfacial electronic structure of the present Si nanoparticles is significantly different with that of alkyl-terminated bulk Si surface. From these results, we discuss the detailed electronic and surface chemical properties of alkyl-passivated Si nanoparticles.