Microbial fuel cells (MFCs) are part of cutting-edge technology that harnesses the power of microorganisms to generate electricity. It is revolutionizing the way we think about sustainable energy. By utilizing bacteria and other microorganisms, microbial fuel cells can convert organic matter into electrical energy with remarkable efficiency, making it a promising solution to overcome modern-day energy challenges. From reducing carbon emissions to providing access to electricity in remote areas, microbial fuel cells have the potential to transform the energy landscape.
In this blog, we'll explore the ins and outs of microbial fuel cells and how this technology can help overcome the energy and environmental issues we face today. So, buckle up and let's dive into the world of microbial fuel cells!
MFCs produce electricity by consuming the electrons from biochemical reactions that are catalyzed by bacteria under anaerobic conditions for a regenerative process. By using microorganisms to convert chemical energy into electrical energy, in an MFC, chemical energy is converted to electrical energy. Exoelectrogens are bacteria that are present in MFCs, which deliver electrons to the anode by three means.
MFCs can be grouped into two general categories: mediated and unmediated. In the early 20th century, the first MFCs were demonstrated using a substance called a mediator that works as an intermediary in the transmission of electrons from the cell's bacterial inhabitants to the anode. In the 1970s, unmediated MFCs were introduced. This form of MFCs has bacteria typically having cytochromes, which are electrochemically active proteins that are present on their outer membranes with the aid of which electrons are directly transferred to the anode. MFCs have come into commercial use for wastewater treatment in the 21st century. These electrochemical cells consist of a bioanode or a biocathode as its core element. The anodic and cathodic chambers are often separated by a membrane in MFCs. Either an electrode or a redox mediator species gets the electrons generated during oxidation directly. The cathode is reached by the electron stream. By intracellular ion transport, which most often happens via ionic membranes, the system's charge balance is maintained.
The majority of MFCs use organic electron donors that are oxidized to produce CO2, protons, and electrons. A microbial fuel cell produces dc millivolts. Each anode electrode has a macro surface area of 270 cm2 (30 × 9 cm). As both a membrane and an anode chamber, these 9 cm-long ceramic cylinders (internal diameter 24 mm, thickness 2 mm) contain the anode sheet. The MFCs produce the maximum current at a pH of 6.5 in the anode chamber. With an increasing pH difference between anodic and cathodic solutions. Carbon paper, mesh, felt, foam rubber, graphite rod, granules, sheets, and brushes, along with reticulated glassy carbon, are common materials used in MFCs (RVC).
For making MFC successfully functional and applicable in real-life scenarios, we must focus on the scaled-up modules through compressing the design footprint to achieve maximum electrical output. To warrant the prolonged duration of the system, its internal and external components should defy biofouling, corrosion, and scaling. Enhanced systems should incorporate MFC power management systems to cover energy harvesting and storage systems, such as supercapacitors, to intensify system performance in real-life scenarios.
Our future innovations must be focused on considering and designing such technologies to meet the criteria of high efficiency and low-cost energy in real-world conditions.
Author
Vignesh Mudaliar, Sagar Pawar, Shubham Botre & Dr. Manjusha Dake*
Dr. D. Y. Patil Biotechnology and Bioinformatics Institute,
Dr. D. Y. Patil Vidyapeeth (Deemed to be University)
Tathawade, Pune - 411033, Maharashtra, India.
* manjusha.dake@dpu.edu.in, +91 020 67919444