APPLICATIONS OF RIBOFLAVIN IN ALL-ORGANIC REDOX FLOW BATTERIES

Abstract

Our future energy demands require an affordable and scalable means of storing energy. Although no technology is likely to meet all of our needs, electrochemical energy storage is a highly efficient method of storing and converting electrical energy. Redox flow battery technology promises to meet the needs of a scalable technology due to its basic design in which the battery fuel is wholly in the liquid form. Although redox flow battery technology on a commercial scale today uses vanadium as its primary fuel component, a battery based solely on organic, electroactive species could be far more advantageous in terms of cost, safety, environmental impact, and energy density. The work herein explores the possibility of utilizing the reversibility of riboflavin’s electrochemical behavior as well as its high adsorptive affinity for carbonaceous electrodes as a battery fuel and in activated electrode design. Considering the size of riboflavin’s molecular structure and the fact that it is a conglomeration of several different nitrogenous heterocycles, the electrochemistry of several riboflavin components were probed using electroanalytical instrumentation in order to better understand the electrochemical and adsorptive characteristics of the parent molecule. Cyclic voltammetry was used as the primary means of evaluating the significance of each riboflavin constituent. Furthermore, it was of interest to utilize riboflavin’s observed adsorptive affinity for graphite electrode surfaces by activating the surface of other carbon-based electrode materials. Carbon paper and carbon black were both explored as conductive scaffolding and activated electrode surface. Riboflavin and nafion, an ion-conducting, polymeric binder was used to prepare activated electrodes using various preparation techniques. The end result of these studies was a better understanding of riboflavin’s physical and electrochemical properties as well as promising starting point for future, activated electrode designs.