Kinetics and mechanism of laser-driven powder synthesis from organosilane precursors

Abstract

Laser-driven synthesis of refractory powders from the organosilicon compounds ((CH3)3Si)2NH and ((CH3)3Si)2O has been studied as prototypical of powder syntheses from large molecules. A cw CO2 laser is used for powder syntheses and pulsed TEA CO2 laser-driven homogeneous pyrolysis is used to study the initiation chemistry. Initial decomposition of the organosilanes by Si–C bond cleavage initiates free radical chain reactions which produce organosilicon polymers and subsequent refractory phases. A qualitative model is proposed which provides a framework for understanding the parameters influencing powder synthesis from large molecules.