Direct gas-phase synthesis of single-phase β-FeSi2 nanoparticles

Abstract

For the first time, phase-pure β-FeSi2 nanoparticles were successfully produced by gas-phase synthesis. We present a method to fabricate larger quantities of semiconducting β-FeSi2 nanoparticles, with crystallite sizes between 10 and 30 nm, for solar and thermoelectric applications utilizing a hot-wall reactor. A general outline for the production of those particles by thermal decomposition of silane and iron pentacarbonyl is provided based on kinetic data. The synthesized particles are investigated by X-ray diffraction and transmission electron microscopy, providing evidence that the as-prepared materials are indeed β-FeSi2, while revealing morphological characteristics inherent to the nanoparticles created.