Silicon-Based Composite Photocatalyst for Solar-Driven Photocatalytic Water Purification

In this work, we report the fabrication of a relatively efficient, cheap, and stable silicon-based photocatalyst for water purification. Silicon-nickel composites were fabricated by mixing and grinding metallurgical silicon with commercial nickel nanoparticles. Experiments demonstrate a significant improvement in methylene blue degradation under UV—and especially under solar—conditions. About half of the contaminants were degraded after 100 min. Theoretical modeling demonstrates the effects of impurities in subsurface layers on absorbance and on the release of hydroxyl radicals from silicon.