SUMMARY

Organic materials with redox-active oxygen functional groups are of great interest as electrode materials for alkali-ion storage application due to their earth-abundant constituents, structural tunability, and enhanced energy storage properties. They are considered promising candidates to overcome the challenges associated with conventional inorganic electrode materials including high cost, limited natural reserves of rare earth metals, and environmental impact. However, the deficient charge conductivity and poor structural integrity in electrolyte solutions significantly limited the utilization of organic materials in electrochemical energy storage systems. Therefore, it is critical to design highly conductive and stable organic frameworks for the development of next-generation organic batteries. In this study, reduced graphene oxide (rGO) with highly defective and hierarchically porous 3D structures were synthesized via subtractive and additive approaches. The controlled modifications upon rGO under solvothermal conditions including chemical etching and hybridization of carbon quantum dots (CQDs) were found to induce significant differences in physical and chemical aspects of the carbon structure, and systematic studies were undertaken to investigate the redox mechanisms of these materials with alkali-ions. Enhanced electrochemical performance was demonstrated for both alkali-ion cathodes and anodes, and the unique impact of electrode nanostructure and surface morphology were distinguished for each application. The findings offer insight into next-generation organic electrode design and charge storage optimization.