Nanoscale energy: unveiling the super-capacitive prowess of graphitic carbon nitride–carbon dots–yttria as GCY nanocomposites for sustainable energy electrode

This study involves the preparation of graphitic carbon nitride (G), carbon quantum dots (C), and yttrium oxide (Y) to synthesize GCY nanocomposites. The synthesis process includes two steps: ultrasonication and hydrothermal treatment. The resulting nanocomposites are then evaluated for their super-capacitive performance using a GCY working electrode. The nanocomposites are analyzed using FTIR, FESEM, and HRTEM to confirm their proper synthesis and are then used as electrode materials for electrochemical energy storage. 0.6 GCY, a composite material, has demonstrated a significant specific capacitance of 378.47 F/g, along with an energy density of 18.17 Wh/kg at a power density of 681.4 W/kg. This makes it a highly promising composite electrode for electrical energy-consuming devices, serving as a reliable energy backup. In addition, the 0.6 GCY had an impressive retention rate of 91.54% after undergoing 5000 cycles. Thus, the GCY electrode, which is easily synthesized, exhibits excellent potential for energy storage in supercapacitor applications. This is attributed to its favorable production process, impressive CV and GCD values, and remarkable capacitive retention.