RESUMO
Photo-assisted microbial fuel cells (PMFCs) are novel bioelectrochemical systems that employ light to harvest bioelectricity and efficient contaminant reduction. In this study, the impact of different operational conditions on the electricity generation outputs in a photoelectrochemical double chamber configuration Microbial fuel cell using a highly useful photocathode are evaluated and their trends are compared with the photoreduction efficiency trends. As a photocathode, a binder-free photo electrode decorated with dispersed polyaniline nanofiber (PANI)-cadmium sulphide Quantum Dots (QDs) is prepared here to catalyse the chromium (VI) reduction reaction in a cathode chamber with an improvement in power generation performance. Bioelectricity generation is examined in various process conditions like photocathode materials, pH, initial concentration of catholyte, illumination intensity and time of illumination. Results show that, despite the harmful effect of the initial contaminant concentration on the reduction efficiency of the contaminant, this parameter exhibits a superior ability for improving the power generation efficiency in a Photo-MFC. Furthermore, the calculated power density under higher light irradiation intensity has experienced a significant increase, which is due to an increment in the number of photons produced and an increase in their chance of reaching the electrodes surface. On the other hand, additional results indicate that the power generation decreases with the rise of pH and has witnessed the same trend as the photoreduction efficiency.
