Fabrication of ZnSe/C Hollow Polyhedrons for Lithium Storage

ZnSe has got extensive attention for high-performance LIBs anode due to its remarkable theoretical capacity and environmental friendliness. Nevertheless, the large volume variation for the ZnSe in the discharge/charge processes brings about rapid capacity fading and poor rate performance. Herein, ZnSe/C hollow polyhedrons are successfully synthesized by selenization of zeolitic imidazolate framework-8 (ZIF-8) with resorcinol-formaldehyde (RF) coating. The protection of C layer derived from RF coating layer and Ostwald ripening during the process of selenization play important roles in promoting formation of ZnSe/C hollow polyhedrons. The ZnSe/C hollow polyhedrons exhibit good rate performance and long-term cycle stability (345 mAh g(-1) up to 1000 cycles at 1 A g(-1)) for lithium ion batteries (LIBs) anode. The improved electrochemical performance is benefit from the unique ZnSe/C hollow structure, in which the hollow structure can effectively avoid terrible volume expansion, and the thin ZnSe/C shell can not only provide adequate diffusion paths of lithium ions and but also enhance the electronic conductivity.

Automated summary

The ZnSe/C hollow polyhedrons with RF coating demonstrate good rate performance and long-term cycle stability for lithium ion batteries (LIBs) anode, achieving a capacity of 345 mAh g(-1) up to 1000 cycles at 1 A g(-1). The enhanced electrochemical performance of the ZnSe/C hollow structure is attributed to the protection from the C layer derived from the RF coating and Ostwald ripening during the process of selenization, which promote the formation of the hollow polyhedrons.