Self-propagating combustion synthesis of nanostructured particles
Apart from the comprehensive investigations of nano-aluminium particle, silicon and boron are also suitable for nano-energetic compositions, but less investigated. Silicon and boron in combination with different oxidizers yield in efficient composite materials with optimized burning properties. The great reactivity of nanoscale particles is mainly based on their high surface-to-volume-ratio. Porous micrometre-scaled particles with high surface areas should feature similar properties compared to nanoscale particles. Advantages are a much better handling and a distinct lower hazard classification. In this work, silicon and boron powder with high surface area were synthesized by self-propagating combustion synthesis (SPCS). The characterization of both products (Si, B) was performed using different methods (Raman spectroscopy, XRD, SEM). After washing with hydrochloric acid (10% HCl), the received combustion products showed a high-purity silicon or amorphous boron with a porous sponge-like structure. The particle size ranged between 30 mm - 100 mm.