Development of ZrO2, V2O5 co-doped carbon nanosheets from green and template-free method for supercapacitor applications

Novel nanoporous carbon sheets (NPCS) intercalated Zr/V ₂O ₅ nanocomposite with various proportions (2:2:1, 1:1:1.5, 1:1:1, 1:1:0.8 and 1:1:0.6) were successfully synthesized through a simple and costeffective sol-gel approach.The nanoporous carbon was prepared from pistachio nutshell by using KOH activation method. The XRD experimental results reveal that the synthesized nanocomposite has high crystalline nature. The surface topology exhibits that well intercalated on the nanoporous carbon surface. The optical analysis showed that the band gap of the nanocomposite was reduced from 1.77 eV to 1.39 eV by increasing the zirconia concentration.N ₂ adsorption and desorption curves reveal that the surface areas of NPCS are 184.20 m ²/gand NPCS intercalated Zr/V ₂O ₅ are 157.22 m ² /grespectively.The electrochemical behaviour of synthesizednanocomposite was measured using Cyclic voltammetry (CV) and Galvanostatic Charge and Discharge (GCD) technique in 1 M Na ₂SO ₄ electrolyte solution of three electrode setup.NPCS and NPCS intercalated Zr/V ₂O ₅ exhibit greater specific capacitance of 243 F g ⁻¹ and 159 F g ⁻¹ at scan rates of 2mVs ⁻¹, respectively, due to their distinctive surface properties and also performs the excellent Cycle stability of 95.9% and 93.5% after 2000 cycles at a scan rate of 2 A g ⁻¹ in the potential range of − 0.2–0.8 V. From the results, it is evident that the synthesized nanocomposite shows excellent potential for supercapacitor applications.