Mechanisms and effects of various reducing agents on the fabrication of elemental boron

Elemental boron powder was fabricated by high-energy ball milling of powder mixtures containing stoichiometric amounts of boron oxide as boron source and magnesium, calcium and aluminum as reducing agents. The reaction was carried out by Spex 8000 D Mixer/Mill with a rotation speed of 1200 rpm with different ball-to-powder weight ratios in the range of 10:1 to 30:1. The effects of milling durations, reducing agents and ball-to-powder weight ratios on the production efficiency of elemental boron were investigated. The milled products include the mixture of boron, borates and oxides which can be removed by selective acid leaching. Eventually, elemental boron in amorphous structure was obtained. Characterization studies of the milled and leached products were performed by X-ray Diffraction technique (XRD) and Atomic Absorption Spectrometer (AAS).