Four lithium coordination polymers, [Li₃(BTC)(H₂O)₆] (1), [Li₃(BTC)(H₂O)₅] (2), [Li₃(BTC)(μ₂-H₂O)] (3), and [Li(H₂BTC)(H₂O)] (4) (H₃BTC = 1,3,5-benzenetricarboxylatic acid), have been synthesized and characterized. All the structures have been determined using single crystal X-ray diffraction studies. Complexes 1 and 2 have two-dimensional (2-D) sheets, whereas complex 3 has three-dimensional (3-D) frameworks and complex 4 has one-dimensional (1-D) tubular chains. The crystal-to-crystal transformation was observed in 1⁻3 upon removal of water molecules, which accompanied the changes in structures and ligand bridging modes. Furthermore, the electrochemical properties of complexes 3 and 4 have been studied to evaluate these compounds as electrode materials in lithium ion batteries with the discharge capacities of 120 and 257 mAhg-1 in the first thirty cycles, respectively.
Keywords: coordination polymers; electrochemical properties; framework structures; lithium.