Synthesis of copper benzene-1, 3, 5-tricarboxylate metal organic frameworks with mixed phases as the electrode material for supercapacitor applications

Copper [email protected], 3, 5-tricarboxylate ([email protected]) metal organic frameworks with two mixed phases (Cu3(BTC)2∙3H2O + {[Cu(BTC-H2)2∙(H2O2]∙3H2O}) are synthesized in water solvent at different temperatures. The crystalline nature, porosity and morphology of prepared products are characterized by X-ray diffraction, Brunauer–Emmett–Teller surface analyzer and transmission electron microscope, respectively. The formation mechanism of these two mixed phases has been proposed, and the electrochemical measurements of the [email protected] MOFs are carried out for electrode material of supercapacitors. The [email protected] electrode shows significant enhancement of specific capacitance compared with other [email protected] electrodes. A maximum specific capacitance of 228 F g−1 has been obtained at a current density of 1.5 A g−1 and long cyclic stability up to 3000 cycles with capacitance retention of ∼89.7% has been achieved for [email protected] electrode. The fast transportation of the electrolyte ions in substantial voids space between octahedral micro-crystals (Cu3(BTC)2∙3H2O) and micro-rods ({[Cu(BTC-H2)2∙(H2O2]∙3H2O}) of [email protected] has greatly improved the electrochemical performance.