Template Synthesis of Monodisperse Submicrometer Spherical Nanoporous Silicon Particles

Abstract

Monodisperse spherical nanoporous silicon (np-Si) particles of submicrometer size are fabricated with mesoporous silica particles as a template. Silicon is synthesized within the mesopores of monodisperse silica particles by the thermal decomposition of monosilane. Then, the template material (a-SiO₂) is removed by wet etching. The particles obtained have a small root-mean-square size scatter (no more than 10%) and large specific surface area (250 m² g^–1) and pore volume (0.5 cm³ g^–1). It is shown that np-Si particles exhibit photoluminescence in the visible and near-IR (infrared) spectral ranges.