TiO2 quantum dots decorated Si nanocage for enhanced lithium ion batteries

The synergetic effect of two or more electrochemically active materials usually leads to superior lithium-ion storage performance. TiO2 quantum dots (TiO2 QDs) decorated Si nanocage composites have been synthesized and used to improve the lithium-ion storage capability. Reversible charge capacity of 616.3 mAh/g was demonstrated over 500 cycles at 1.0 A/g and Li storage capacities of 513.6 mAh/g was retained at 10.0 A/g after 150 cycles. The desirable charge capacities, cyclic ability and rate performance of Si-TiO2 can be ascribed to the special Si nanocage for buffering volume expansion and the ultra-small TiO2 helpful for shortening ion transfer pathway, ensuring Li+ capture as well as accelerating electrode reaction, and modifying interfacial of Si to maintain the electrode integrity. This work maybe provides a valuable insight to the synthesis of functional interlayers suitable for applications in LIBs.