One-step synthesis of dual-ligand 2D conductive metal-organic framework for high-performance lithium storage

Abstract

Two-dimensional conductive metal-organic frameworks (2D c-MOFs) are emerging as promising electrode materials for lithium-ion batteries (LIBs). However, 2D c-MOFs with binary redox-active organic ligands are rare and suffer from complicated synthesis procedures. Herein, a facile one-step method is developed for the synthesis of a dual-ligand-based 2D c-MOF Cu3(HHTP)(THQ) (HHTP = 2,3,6,7,10,11-hexahydroxytriphenyl, THQ = tetrahydroxy-1,4-benzoquinone) by using the ethylenediamine regulator. The resulting Cu3(HHTP)(THQ) possesses good conductivity, abundant active sites, and excellent chemical stability. As an anode material for LIBs, Cu3(HHTP)(THQ) exhibits high specific capacity, good rate performance, and long-term cycling stability. Comprehensive experimental studies and theoretical calculations reveal that CuO4 units and aromatic benzene rings in Cu3(HHTP)(THQ) are involved in lithium storage, thereby optimizing the lithium storage performance. This work provides a new way for the construction of dual-ligand 2D c-MOFs and high-performance LIB electrode materials.[Figure not available: see fulltext.]