Synthesis and Optical Characterization of Silole Derivatives and Silicon Nanoparticles

Abstract

Part 1 Nanocrystalline porous silicon surfaces have been used to detect nitroaromatic compounds in vapor phase. The mode of photoluminescence is emphasized as a sensing attitude or detection technique. Quenching of photoluminescence from nanocrystalline porous surfaces as a transduction mode is measured upon the exposure of nitroaromatic compounds. Reversible detection mode for nitroaromatics is, too, observed. To verify the detection afore-mentioned, photoluminescent freshly prepared porous silicons are functionalized with different groups. The mechanism of quenching of photoluminescence is attributed to the electron transfer behaviors of quantum-sized nano-crystallites in the porous silicon matrix to the analytes (nitroaromatics). An attempt has been done to prove that the surface-derivatized photoluminescent porous silicon surfaces can act as versatile substrates for sensing behaviors due to having a large surface area and highly sensitive transduction mode. Part 2 We describe the synthesis and characterization of silicon nanoparticles prepared by the soluton reduction of SiCl4. These reactions produce Si nanoparticles with surfaces that are covalently terminated. The resultant organic derivatized Si nanoparticles as well as a probable distribution of Water-soluble Si nanoparticles are observed and characterized by photoluminescence(PL) spectroscopy. This work focuses originally on the organic- and water-soluble silicon nanoparticles in terms of the photoluminescence. Further this work displays probably the first layout of hydrogen terminated Si nanoparticles synthesized in solution at room temperature. Part 3 The silole derivatives (dibenzosiloles or the silafluorenes) i.e. 1,1-dichloro-1-silafluorene and 1,1-dimethyl-1-silafluorene as well as 9,9'-spiro-9-silabifluorene compounds were synthesized from 1,2-dibromobenzene, n-butyllithium and silicon tetrachloride in higher yields characterized by NMR spectroscopy. The dibenzosiloles are expected to be efficient host materials for the blue-light emitting diodes.