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Metal–organic frameworks (MOFs) derived nanostructures receive immense research focus due to its high porosity, conductivity, and structural tailrolability features. In this work, porous Zeolitic Imidazole Framework‐67 (ZIF‐67) to synthesize cobalt phosphide/carbon composite (ZCoPC) that serves as a positive electrode is utilized. Furthermore, porous and conductive office paper derived carbon (OPC) are utilized as a negative electrode to make a hybrid system. The metalloid characteristics, high conductivity, and good porosity of ZCoPC material makes it a high‐performance battery like electrode. ZCoPC electrode achieves maximum specific capacity of 192.6 mAh g−1 at 1 A g−1 using 1 m potassium hydroxide (KOH) electrolyte. Furthermore, surface and diffusion charge participation investigation are also undergone for ZCoPC electrode that helps in determining the actual charge dynamics occurring in the electrode. In addition, a supercapattery device is assembled using ZCoPC as battery electrode and OPC as supercapacitor electrode. The as fabricated OPC//ZCoPC hybrid supercapattery device delivers extraordinary energy density of 31.6 Wh kg−1 with a power density of 700 W kg−1 and also a long cycle life of 92.3% even after 10,000 charge–discharge cycles. Hence, these outcomes demonstrate that the synergy of porous MOF derived metal phosphide and OPC electrodes are beneficial for supercapattery devices. [ABSTRACT FROM AUTHOR]

Abstract The role of redox additive electrolytes in supercapacitors is gaining an increased significance. The present research work, for the first time, investigates the supercapacitor performance of a rGO/TiO 2 nanosheet composite (prepared via facile one step hydrothermal reaction route) electrode in combination with a redox additive electrolyte, i.e., 0.2 M K 3 [Fe(CN) 6 ] in 1 M Na 2 SO 4. The synergistic effects between the porous rGO/TiO 2 nanosheet electrode and the optimized redox electrolyte have helped to achieve a significantly high specific capacitance of 1565 F/g at a current density of 3 A/g (working potential window = −0.1–0.5 V). This value of specific capacitance is much higher than achievable with the application of a plain aqueous electrolyte (e.g., 1 M Na 2 SO 4). Furthermore, rGO/TiO 2 nanosheet electrodes have been used to fabricate a symmetrical supercapacitor device which has delivered an excellent specific capacitance value of 204.5 F/g at a current density of 1.5 A/g. The device also yielded promising values of energy density (15.5 Wh/kg) and power density (1.1 kW/kg) apart from showing a long-term cyclic stability (∼87%) even after 1000 continuous charge-discharge cycles. Graphical abstract Image 1 Highlights • A composite of rGO/TiO 2 nanosheets has been explored as a supercapacitor electrode. • 0.2 M K 3 [Fe(CN) 6 ] in 1 M Na 2 SO 4 has been used as an optimized electrolyte. • Selection of above electrode and electrolyte yielded high specific capacitance. • A specific capacitance of 1565 F/g has been achieved at a current density of 3 A/g. • High values of energy (15.5 Wh/Kg) and power (1.1 kW/kg) densities were achieved. [ABSTRACT FROM AUTHOR]