Humic acid-based interlocked MOF: Enabling stable cycling performance at ultra-high current densities for lithium-ion batteries

Nowadays, metal-organic frameworks (MOFs) are regarded as promising anode materials for lithium-ion batteries (LIBs) due to their high porosity, tunable structure, and considerable surface area. However, limited by low conductivity and poor cycling stability, few MOF-based anodes can achieve stable cycling performance at high current densities for practical applications. Herein, we report the preparation of a unique interlocked smoothie-like anode material, named HA-Co-BPDC, for lithium-ion batteries through a facile two-step hydrothermal method. The as-prepared HA-Co-BPDC anode exhibits outstanding reversible capacity of 1603 mAh g−1 at 0.1 A g−1 and remains 971 mAh g−1 at 1 A g−1, exhibiting good rate capability. Most importantly, the HA-Co-BPDC anode shows excellent long-term cycling stability at ultra-high current density, due to the unique interlocked structure which endows high tolerance toward the volume expansion/contraction. Typically, specific capacities of 315 and 242 mAh g−1 are obtained after 1000 cycles at 5 and 10 A g−1, which delivers high capacity retention of 84% and 80%, respectively. Possessing outstanding reversible capacity, good rate capability, and excellent long-term cycling stability at ultra-high current density, the HA-Co-BPDC exhibits great potential in practical applications.