An amorphous Si material with a sponge-like structure as an anode for Li-ion and Na-ion batteries

Sponge-like amorphous silicon was prepared by reacting silicon tetrachloride with magnesium powder. When the as-prepared sample was applied as an anode in rechargeable batteries, it exhibited a reversible capacity of 1125 mA h g(-1) after 100 cycles at 1 A g(-1) for Li-ion batteries (LIBs) and a reversible capacity of 176 mA h g(-1) at 100 mA g(-1) over 100 cycles for Na-ion batteries (NIBs).