A sustainable route from fly ash to silicon nanorods for high performance lithium ion batteries

The practical application of silicon based anode for lithium ion batteries is severely limited by the fabrication process of Si nanomaterials, which is complex, costly, and high energy-consuming. Here silicon nanorods have been synthesized from industrial waste fly ash by electrospinning and modified magnesiothermic reaction. The whole process is simple, cost-effective, green and easy to scale-up. While used as an active electrode material in a lithium battery, the obtained silicon nanorods anode exhibits a remarkable lithium storage performance: under the current density of 0.5 C, it could deliver reversible capacity as high as 1136.8 mAh g(-1) after more than 100 cycles. The attractive electrochemical performance of the silicon nanorods is attributed to its 1D nanostructure, porosity and outward nanometer-sized SiOx layer. Meanwhile, the present research makes it possible to accomplish the high-valued application of fly ash and other dust contaminants.