Exploring the Optical and Energetic Properties of a Co(II)-Based Mixed Ligand MOF

Abstract

Due to their remarkable properties, including remarkable porosity and extensive surface area, metal−organic frameworks (MOFs) are being investigated for various applications. Herein, we report the first Co(II)-based mixed ligand MOF, formulated Co 4 (HTrz) 2 (D-cam) 2.5 (μ−OH) 3 . Its 3D structure framework is composed of helical chains {[Co 4 (μ 3 -HTrz) 4 ] 8+ } n connected by D-camphorate ligand building blocks and featured as an extended structure in an AB−AB fashion. The investigated compound displays a wide absorption range across the visible spectrum, characterized by an optical gap energy of 3.7 eV, indicating its semiconducting nature and efficient sunlight absorption capabilities across various wavelengths. The electrochemical performance demonstrated an excellent reversibility, cyclability, structural stability, as well as a specific capacity of up to 100 cycles at a scan rate of 0.1 mV•s −1 and a current density of 50 mA•g −1 . Thus, it showcases its ability to retain the capacity over numerous charge−discharge cycles. Additionally, the investigated sample displayed an impressive rate capability during the Liion charge/discharge process. Therefore, the material's remarkable electrochemical properties can be ascribed to the synergistic effects of its large specific surface area of 348.294 m 2 •g −1 and well-defined pore size distribution of 20.448 Å, making it a promising candidate for high-performance Li-ion batteries.