Physical Sciences and Mathematics Commons^™

Surface Modification Of Carbon-Based Electrodes For Electrochemical Conversion Processes: Oxygen Reduction Reaction And Bicarbonate Conversion, Udari Shyamika Kodithuwakku Arachchige

Theses and Dissertations--Chemistry

Oxygen reduction reaction (ORR) and conversion of bicarbonate into value-added chemicals are two significant electrochemical processes for energy storage and conversion. ORR is an important electrochemical reaction in fuel cells and metal-air batteries that provide power conversion and storage capacity, respectively, for portable electronics, and electric vehicles. However, the performance of catalysts (e.g., platinum-based) is critically limited by slow kinetics, inefficient four-electron pathway, and surface deactivation. This limited performance of platinum-based catalysts, the scarcity of platinum, and vulnerable supply chains for critical minerals require the development of alternative electrocatalysts now more than ever. Carbon-based materials possess several key properties that …

Carbon Quantum Dots: Bridging The Gap Between Chemical Structure And Material Properties, Timothy J. Pillar-Little Jr.

Theses and Dissertations--Chemistry

Carbon quantum dots (CQDs) are the latest generation of carbon nanomaterials in applications where fullerenes, carbon nanotubes, and graphene are abundantly used. With several attractive properties such as tunable optical property, edge-functionalization, and defect-rich chemical structure, CQDs have the potential to revolutionize optoelectronics, electro- and photocatalysis, and biomedical applications. Chemical modifications through the addition of heteroatoms, chemical reduction, and surface passivation are found to alter the band gap, spectral position, and emission pathways of CQDs. Despite extensive studies, fundamental understanding of structure-property relationship remains unclear due to the inhomogeneity in chemical structure and a complex emission mechanism for CQDs.

This …