Boosting lithium storage performance of diatomite derived Si/SiOx micronplates via rationally regulating the composition, morphology and crystalline structure

Nano- and micro-sized silicon and its low valence oxide show as one of the potentially promising anode materials for lithium-ion batteries (LIBs) with high energy density . Even so, the high price of nanosized silicon and poor tolerance against mechanical stress of microsized silicon limit their practical applications as silicon anode materials. Herein, using diatomite, a naturally occurring siliceous sedimentary rock , as a precursor, a series of porous Si/SiO x micronplates are synthesized through magnesiothermic reduction followed by an acid etching process. When evaluated as LIB anodes, the Si/SiO x micronplates exhibit significant improvement of cycle stability compared to commercial silicon anodes. Moreover, etched Si/SiO x micronplates achieve a highly reversible lithium storage capacity of 980 mAh g -1 at 100 mA g -1 after 100 cycles, which is over two times as high as unetched Si/SiO x anodes. The boosting lithium storage performance is attributed to the rational regulations of composition, morphology, and crystalline structures of microsized Si/SiO x , which demonstrate that the as-prepared Si/SiO x micronplates should be a series of promising anode materials for high energy density LIBs.