Metal-Organic Framework-Structured Porous ZnCo2O4/C Composite Nanofibers for High-Rate Lithium-Ion Batteries

In this work, metal-organic framework (MOF)-structured porous ZnCo2O4/C composite nanofibers are prepared by electrospinning, followed by in situ growth and annealing. The ZnCo2O4/C nanofibers exhibit features such as robust pores, high specific surface area (148.7 m2·g-1), and nanofiber structure, enabling excellent capacity performance, cycle stability, and rate capabilities as anode in lithium-ion batteries (LIBs). Briefly, specific discharge capacities of 1707 and 1145 mAh·g-1 are delivered for initial and after 100 cycles, respectively, and even restraining a specific capacity of 701 mAh·g-1 at 1.0 A·g-1. The excellent electrochemical properties of MOFs-ZnCo2O4/C composite nanofibers are mainly attributed to the following reasons: (i) the abundant channels for lithium-ion intercalation/de-intercalation offered by the MOF structure; (ii) the alleviated volume expansion during the charge/discharge process owing to the intrinsic stability of the one-dimensional (1D) fiber; and (iii) the carbon fiber with excellent conductivity enables efficient conduction efficiency of lithium ions and electrons. Capacity fading is significantly improved, and the proposed strategy offers a perspective to improve electrochemical performance in energy storage.