Metal-Dependent Lithiation Behaviors in Cobalt and Zinc Metal–Organic Frameworks as Lithium-Ion Battery Anodes

Metal–organic frameworks (MOFs) have emerged as structurally designable materials for lithium-ion batteries (LIBs) due to their tunable coordination architecture and functionality. Herein, we report a couple of isostructural MOFs of divalent cobalt (1) and zinc (2), [MII2(bdc)2(DABCO)]n, [bdcH2 = terephthalic acid, DABCO = 1,4-diazabicyclo[2.2.2]octane], and evaluate their lithium storage performance. Electrochemical properties and performance show that Co-MOF 1 has higher efficiency than the Zn congener, with an excellent specific capacity of 750 mAh g–1 after 10 cycles and last at 322 mAh g–1 after 200 cycles, which is a high electrochemical performance in specific capacity and rate cycle performance over the previous MOF-based materials. The ligand substitution at the metal centers of the MOFs triggered the single-crystal to single-crystal transformation toward corresponding [MII(H2O)(bdc)(DABCO)]n (1a and 2a) MOFs, which were investigated. First-principles computations revealed that the identity of the metal center critically governs the lithiation behavior of these MOFs.