Microstructurally assembled transition metal oxides with cellulose nanocrystals for high-performance supercapacitors

Owing to the rapid growth in fossil fuel consumption and the related ecological concerns, alternative routes such as green energy and efficient storage technologies have been developed; many technologies require the fabrication of supercapacitor devices. Cellulose nanocrystals (CNCs) can be used to make composites; their structural, morphological, and mechanical properties result in high-performance sensors, supercapacitors, and electrocatalysts. Cellulose nanocrystal (CNC) materials are promising sustainable and environmentally friendly candidates for the development of green and renewable electronics for energy conversion processes. In this study, hierarchical CoFe2O4@CNC nanocomposite was synthesized to prepare electrodes for supercapacitors, also prepared the pristine CoFe2O4 sample for comparison. The composite materials were characterized with different techniques to determine the structural, morphological, surface, and electrochemical characteristics. Furthermore, the electrochemical characteristics were examined with CV, GCD, and EIS studies to assess the suitability for supercapacitor applications. The synthesized nanocomposite materials exhibit improved electrolyte/electrode surfaces, which promote the diffusion of ions. The CoFe2O4@CNC nanocomposite has 629 F/g capacitance at 0.5 A/g and retains 95.8% capacitance after 5000 cycles. Therefore, the creation of highly active electrochemical sites via the incorporation of CNC improves the capacitive performance of devices.