Low-temperature hydrothermal activation-catalytic carbonation boosting porous Si/SiOx@C composites derived from bamboo leaves for superior lithium storage performance

Silicon oxides are considered as one of the most attractive anode materials of the high energy-density lithium-ion batteries (LIBs) owing to their high theoretical specific capacity and abundant reserves. In this study, a facile low temperature hydrothermal activation-catalytic carbonation and mild aluminothermic process have been developed to prepare porous Si/SiOx@C composite with fresh bamboo leaves as low-price raw materials. When evaluated as an anode material in LIBs, the as-prepared hierarchical porous Si/SiOx@C composite achieves a high capacity of 1075 mAh g-1 after 350 cycles under the current density of 200 mA g-1. Moreover, the good dispersion of the Si/SiOx matrix in porous carbon guarantees outstanding rate performances of the electrodes. When the current density increases to 1000 mA g-1, the considerable specific capacity of 470 mAh g-1 can be obtained after 450 cycles. This strategy opens a new avenue for economical and low-technology demanding preparation of multifunctional biomass-based anode materials for the next generation LIBs.