Hericium erinaceus-like Copper-Based MOFs as Anodes for High Performance Lithium Ion Batteries

Most of the pristine metal-organic frameworks (MOFs) used as anodes have challenges including the structural stability and conductivity of the electrode, and the electrochemical performance of the batteries can be tailored by the morphology of the MOF materials. In this work, a Hericium erinaceus-like copper-based MOF (HECM) with a hierarchical structure is in situ synthesized via a one-step hydrothermal method under the assistance of citric acid as the ligand. The introduced polyvinylpyrrolidone (PVP) as the structure tuner modifies the stacking arrangement of MOF nanosheets to obtain a Hericium erinaceus morphology. This hierarchical structure can effectively release stress and enhance the structural stability of the electrode during long cycling. Additionally, it can provide sufficient intense and short transportation paths for lithium ion diffusion to improve the conductivity of the electrode. Herein, by using this pristine HECM material as the anode, an initial discharge capacity of 1205.9 mA h g(-1) is achieved at a current density of 100 mA g(-1). The discharge capacity remains at 897 mA h g(-1) after 150 cycles, which is 74.4% of the initial discharge capacity. Moreover, this MOF synthesis approach is simple, low-cost, and environmentally friendly. Thus, the green preparation method and excellent properties of the HECM would inspire the development high-performance MOFs for lithium ion batteries.

Automated summary

In this study, a hierarchical copper-based MOF resembling Hericium erinaceus was successfully synthesized via a one-step hydrothermal method with the assistance of citric acid. The introduced PVP as a structure tuner modified the stacking arrangement of MOF nanosheets to achieve the Hericium erinaceus morphology, enhancing electrode stability during cycling. The MOF showed promising initial discharge capacity and retained a high capacity after 150 cycles, demonstrating its potential for high-performance lithium ion batteries.