Lanthanide (III) Metal‐Organic Frameworks: Syntheses, Structures and Supercapacitor Application

Abstract

AbstractThree new lanthanide‐MOFs, [(TATMB)2Ce2⋅3DMSO‐H2O]⋅7H2O (MOF−Ce), [(TATMB)2Pr2⋅4DMSO]⋅7H2O⋅DMF (MOF−Pr) and [(TATMB)2Nd2⋅3DMSO⋅H2O]⋅6H2O (MOF−Nd) were synthesized by the reaction of hydrated lanthanide salts and 3,3′,3′′‐((1,3,5‐triazine‐2,4,6‐triyl)tris(azanediyl))tribenzoic acid (H3TATMB) under solvothermal reaction condition. All MOFs were characterized by standard instrumentation techniques, for example, FT‐IR spectroscopy, elemental analysis, etc. The solid‐state structures were determined by single‐crystal X‐ray diffraction analyses. It revealed that all MOFs formed two‐dimensional frameworks by the coordination assisted pathway of ligand molecules and lanthanide(III) ions. All MOFs were investigated as supercapacitor electrode material by using the conventional three‐electrode method by using TEABF4 in acetonitrile as electrolyte. It was observed that MOF−Ce exhibited a maximum specific capacitance of 572 Fg−1 at a current density of 1 A g−1 among all three MOFs. The specific capacitance retention of the material was found to be 81% after successful completion of 5000 charging‐discharging cycles. To the best of our knowledge, the specific capacitance of MOF−Ce is highest reported for lanthanide MOFs without any redox‐active additive until now. Moreover, for the first time, MOF−Ce has been used to fabricate a device, which exhibited significant responses for various LED lights and showed a maximum specific capacitance of 88 Fg−1 at a current density of 2 A g−1.