Hydrothermal Synthesis of RGO/CoAl2O4 Nanocomposite with Enhanced Supercapacitor, Antibacterial and Antifungal Performances

Nanostructures of CoAl2O4 and RGO/CoAl2O4 were synthesized via a hydrothermal method and evaluated using various characterization techniques, including XRD, FTIR, FE-SEM, EDAX, HRTEM, XPS, and CV. XRD analysis revealed that the samples exhibit a cubic crystal structure with an Fd3m space group. The average crystallite sizes of CoAl2O4 nanoparticles synthesized at 6 h and 24 h were determined to be 25 nm and 36 nm, respectively, while the RGO/CoAl2O4 composite exhibited a crystallite size of 51 nm. FTIR spectra indicated a gradual shift and intensification of absorption bands upon incorporating RGO into CoAl2O4. Morphological analysis using FESEM and HRTEM confirmed the formation of porous cubic-shaped nanostructures integrated with RGO nanosheets. Elemental composition was identified through EDAX, while XPS provided a detailed analysis of the chemical states. The CoAl2O4 sample exhibited a maximum specific capacitance of 245 Fg− 1, whereas the RGO/CoAl2O4 nanocomposites achieved a significantly higher value of 410 Fg− 1 at a scan rate of 5 mV s− 1. The antibacterial and antifungal activities of the samples illustrated that the RGO/CoAl2O4 composite demonstrated higher inhibition zones compared to CoAl2O4, indicating enhanced biological efficacy. Overall, RGO/CoAl2O4 composites exhibited improved electrochemical performance for supercapacitor applications and greater biological activity against bacterial and fungal pathogens than their CoAl2O4 counterparts.