Synthesis and gas adsorption, electrochemical characteristic of new (3,6)-connected mixed link Fe(Ⅲ) metal-organic framework

Abstract

A new Fe(Ⅲ) Metal-Organic Framework which we termed MOF-964, [Fe3O(BTB)4/3(NDC)](HCO2)2/3 (H2O)4/3X1/3 (X=OH-1), based on two different linkers, 1,3,5-Tris(4-carboxyphenyl) benzene (H3BTB) and 2,6-Naphthalenedicarboxylic acid (H2NDC), have been synthesized and structurally characterized. The structure of MOF-964 was solved by synchrotron single-crystal X-ray diffraction analysis. MOF-964 is composed of μ3-oxo centered trimer of iron (Ⅲ) octahedra clusters linked by four BTB linkers and two NDC linkers, resulting in a new (3,6)-connected net. The MOF-964 has specific surface area of 2174 m2/g according to the Brunauer-Emmett-Teller method. Thermogravimetric analysis(TGA) shows that MOF-964 has thermal stability up to 300℃ in air. The CO2 isotherm for MOF-964 was performed in the high pressure region under 50 bar at 298K, revealing that the maximum CO2 uptake at 50 torr of MOF-964 is around 10 mmol/g which is almost similar with other MOFs having a open metal center(MOF-74,MOF-505,Cu3(BTC)2). Electrochemical properties of MOF-964 as cathode material of Lithium Ion Battery was investigated to show the potential for application it as active material of energy storage devices. The electrochemical results indicate that MOF-964 has reversible charge-discharge behavior after 1 cycle and specific capacity of 20mAh/g at C/40 rate.