Improved electrochemical performance of nitrogen-containing copper-based 1D metal organic framework derived from highly connective pyridine-2,4,6-tricarboxylic acid for hybrid supercapacitors†

Metal organic frameworks (MOFs) are promising candidates for emergent energy storage devices due to their intrinsic properties, such as rich porosity, variable nano-geometries, and multifunctional characteristics. Here, we report the synthesis of copper-based MOFs (Cu-PTA-MOF), polyaniline (PANI), and polypyrrole (PPY), which have been characterized using different techniques. Pyridine-2,4,6-tricarboxylic acid (PTA) ligands were connected by metal ions through π–d conjugated layers to generate the 1D polymer. Electrochemical attributes of Cu-PTA-MOF@AC, Cu-PTA-MOF@PANI and Cu-PTA-MOF@PPY were explored using a three-electrode assembly with 1 M KOH. Cu-PTA-MOF@PANI exhibited good results. For practical application, it was coupled with an activated carbon electrode in a hybrid supercapacitor device. The device exhibits a specific capacity of 232 C g⁻¹, 72.5 W h kg⁻¹ energy density and 4500 W kg⁻¹ power density at 0.5 A g⁻¹ current density with a coulombic efficiency of 98.8% even after 10 000 GCD cycles. The conductive polymer endowed the material with rapid ion and electron transfer and allowed utilization of the active material in a hybrid supercapacitor.