Optimization of a Photosynthetic Microbial Fuel Cell

Overview

Renewable energy is a critical field of study, and photosynthetic microbial fuel cells (PMFCs) present a relevant and new area of focus in this field. In PMFCs, electrons produced through anaerobic bacterial respiration are transferred via conductive electrodes and accepted by algae. This flow of electrons produces an electrical current. Chemical mediators, such as methylene blue (MB), are necessary to transport electrons between bacterial/algal cells and electrodes, but are costly and unsustainable. Flavins are naturally-produced molecules, which were found to correspond to greater external electron transport. The purpose of this experiment was to evaluate the novel use of riboflavin as a supplemented mediator. Riboflavin was chosen because of the recent development of mass-production of the substance through biosynthesis. It was hypothesized that if riboflavin was added to PMFCs as a natural mediator, then it would lead to better energy production than MB or mediator-less PMFCs. PMFCs were constructed with Spirulina platensis algae and anaerobic bacteria from salt marsh sediment. Then, three sets of trials were conducted, comparing (1) riboflavin and a mediator-less PMFC, (2) riboflavin and MB, and (3) a riboflavin-coated carbon-cloth electrode and a typical PMFC. It was found that PMFCs supplemented with riboflavin were superior to both mediator-less and MB. The riboflavin-coated electrode was also more efficient than the typical PMFC. This project holds important implications for the future of renewable energy by making PMFCs far more accessible and sustainable, and presents a novel method of increasing energy production by PMFCs.

Competition history

AJAS 2020 Category not listed

Related projects

JSHS · 2020