Nitrogen-doped carbon quantum dots (N-CQDs)/Co3O4 nanocomposite for high performance supercapacitor
Mu. Naushad, Tansir Ahamad, Mohd Ubaidullah, Jahangeer Ahmed, Ayman Abdel Ghafar, Khalid M. Alsheetan, Prabhakarn Arunachalam
Abstract
The search of low cost, highly competent electrode material is the hot research area for various next-gen applications. Herein, cost effective nitrogen doped carbon quantum dots (N-CQDs) anchored in cobalt oxide (Co3O4) nanocomposite was fabricated through a simple hydrothermal method. The fabricated N-CQDs/Co3O4 nanocomposite showed high specific surface area (BET) of ~880 m2 g−1 with BJH pore size and volume of ~21 nm, 0.81945 cm3 g−1 respectively. The electrochemical performance through cyclic voltammetry (CV) in 3-electrode systems exhibited an improved specific capacitance of 1782 F g−1 at 5 mV s−1 in 6 M KOH electrolyte. Additionally, galvanostatic charge–discharge (GCD) analysis showed an improved capacitive performance with a specific capacitance of 1867 F g−1 at 1 A g−1 current density. The energy density was calculated 36.9 Wh kg−1 at the power density of 480 W kg−1. The capacitance retention graph demonstrates 96% stability through 500 GCD cycles.