Preparation of Double-Shelled Fluorescent Silicon Nanocrystals and Fabrication of Its Thin Layer by Electrophoretic Deposition Process

Abstract

Here we show an electrophoretic deposition process for a uniform coating of glass substrate surface with fluorescent silicon nanocrystals (SiNCs). The NCs with ∼35% of photoluminescence quantum yields (PLQYs) were synthesized by thermal disproportionation of hydrogen silsesquioxane, followed by hydrosilylation of 1-decence. Next, the hollow-silica particles that are crammed of the decane-terminated NCs were prepared by taking advantage of a vacuum impregnation process. The PL spectra were measured as a function of temperature for films of NCs before and after silica encapsulation. It was observed that a rapid decrease of PL intensity with elevated temperature for the hydrogen-terminated NCs whereas the silica capsule suppresses a thermal quenching to give PL stability at high temperature. The presence of a silica capsule also allows electrophoretic deposition of the NCs to the surface of an ITO glass substrate.