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.

Automated summary

The synergetic effect of TiO2 quantum dots (TiO2 QDs) decorated Si nanocage composites leads to superior lithium-ion storage performance. Reversible charge capacity of 616.3 mAh/g was achieved over 500 cycles at 1.0 A/g, and Li storage capacities of 513.6 mAh/g were retained at 10.0 A/g after 150 cycles. The improved performance of Si-TiO2 can be attributed to the special Si nanocage for buffering volume expansion and the ultra-small TiO2 for shortening ion transfer pathway and modifying the interfacial of Si.