Nano-size silicon particles for the next-generation Lithium-ion batteries could be produced from rice husk, an abundant agricultural waste, according to research recently published in Scientific Reports.
Nano silicon had attracted considerable attention as a promising anode material for such high-performance batteries, which would power future electric vehicles and portable devices, observed Yi Cui, an associate professor of materials science and engineering at Stanford University in the U.S., and his colleagues in their paper.
Although nano silicon anodes were superior to graphite ones in terms of performance, methods to produce the silicon anodes at a cost and with scalability comparable to graphite were needed. Current processes to form silicon nanomaterials were usually complex, costly and energy-intensive, they pointed out. In rice husk, silica existed naturally in the form of nanoparticles and accounted for as much as 20 per cent of its dry weight. Using a simple, energy-efficient and easily scalable method , nano silicon could be produced. The silicon that was recovered maintained the unique nanostructure of silica as it existed in the husk, which made for excellent battery performance.
Apart from its use in Lithium-ion batteries, there were many potential large-scale applications for such nanostructured silicon, they added.