Author ORCID Identifier


Defense Date


Document Type


Degree Name

Doctor of Philosophy



First Advisor

Dr. Hani M. El-Kaderi


As the demand for renewable energy technologies grows, so does the need for cheaper, more efficient rechargeable batteries to store the energy. While lithium-ion battery (LIBs) technology is well established, it suffers from limited lithium supplies. Furthermore, the highly toxic transition metals used in the electrodes places a huge burden on the environment. Therefore, replacing lithium with more economical sodium metal in rechargeable batteries (i.e. sodium-ion batteries, SIBs) has garnered considerable attention. Despite the fact that sodium and lithium share similar electrochemical properties, which may cause the transition from lithium to sodium easier, the larger ionic radius of Na+ (1.02 Å) makes its intercalation into conventional electrode materials, a significant challenge that needs to be addressed through material design.

The use of polymeric redox-active organic material in rechargeable batteries has the potential to transform the field. The highly cross-linked polymers eliminate the dissolution issue of organic electrodes in common electrolytes, that might otherwise lead to fast capacity fading. Additionally, the use of highly porous, high surface area polymers with the π-conjugated structure can facilitate electrolyte adsorption in the pores and assists in high charge storage, fast ion transport, and physicochemical integrity.

This dissertation presents the exploration of new polyimide-based crystalline covalent organic frameworks (COF) as well as highly porous azo-linked polymers (ALPs) as redox-active electrode materials for rechargeable sodium-ion batteries and discusses the mechanistic insights into Na+ ion storage in each of these systems followed by research perspectives and future directions available for research.


© K. Shamara Weeraratne

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission


Available for download on Saturday, May 17, 2025