Mesoporous Nano‐Si Anode for Li‐ion Batteries Produced by Magnesio‐Mechanochemical Reduction of Amorphous SiO2

The synthesis of nano‐sized Si with various microstructures has been studied intensively to produce anode materials for Li‐rechargeable batteries. Methods such as chemical/physical vapor deposition (CVD/PVD) and wet‐chemical processes are currently used to produce nano‐sized Si; however, the complicated synthesis procedures and low production yields are critical problems that hinder commercialization. We present a method for producing large quantities of mesoporous nano‐sized Si through the reduction of amorphous SiO2 with Mg metal, by using a high‐energy mechanical milling process (i.e., magnesio‐mechanochemical processing) for 1 h. A mesoporous nano‐sized Si electrode shows excellent electrochemical performance as an anode for Li‐ion batteries, achieving a capacity greater than 1600 mAh g−1 over 30 cycles.