Nanostructured nickel doped manganese oxide/polypyrrole/graphitic carbon nitride hydrogel as high-performance supercapacitor electrodes

Polypyrrole hydrogel (PH) attributing high electrical conductivity, intriguing redox properties, ease of synthesis and environmental friendliness, is a prospective electrode material for supercapacitors (SCs). This work presented details of the synthesis of pH and its binary and ternary nanocomposites. The ternary nanocomposite PPyGCN-NMO (PGNMO), synthesized via in-situ oxidative polymerization, demonstrates an exclusive combination of morphologies, leading to excellent supercapacitive performance. The strategically chosen synergy of electric double-layer capacitance (EDLC) and pseudocapacitive materials helps in overcoming the limitation of individual elements and collectively accounts for excellent supercapacitive performance. Electrochemical studies of PGNMO electrode provides an excellent specific capacitance (Cs) of 3611 F/g at 1 A/g. Moreover, the fabricated symmetric device of PGNMO exhibits impressive Cs of 588 F/g at 1 A/g, and exceptional cycle stability with 104.3 % retention after 6000 cycles. Additionally, the device delivers appreciable specific energy of 40.1 Wh/kg at 1587.6 W/kg, positioning PGNMO to the forefront of flexible electrodes for SCs.