An iron supramolecular compound containing terpyridine polycarboxylic acid for high performance lithium-ion batteries

A 4-pyridine functionalized terpyridine polycarboxylic acid (HTPYPA = 4'-(pyridin-4-yl)-[2,2':6',2''-terpyr-idine]-4,4''-dicarboxylate) has been designed and synthesized. With this ligand, an iron supramolecular compound (Fe(HTPYPA)(2)) was synthesized by using the coordination-driven self-assembly strategy. Fe(HTPYPA)(2) has been characterized by single-crystal X-ray diffraction, scanning electron microscopy (SEM), X-ray powder diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), and so on. When Fe(HTPYPA)(2) acts as anode material for lithium-ion batteries, it displays the reversible capacity of 650 mAh g(-1) after 300 cycles at the current density of 100 mA g(-1) and excellent cycling stability, which may be ascribed to the synergistic effect between the pi-conjugated terpyridine-based polycarboxylic groups and the introduced Fe(II) ions.