By: Michael Hoe
Microbial fuel cells (MFCs) with innovative new biopolymer composite membranes are able to generate a higher electrical charge than other membranes as well as creating an anaerobic environment that improves the MFC’s efficiency in utilizing wastewater. This provides biopolymer composites new avenues for application in sustainable electricity generation.The ever-increasing demand for sustainable, renewable energy in the face of global warming has led to development of innovative technologies such as microbial fuel cells (MFC).
MFCs are especially attractive as they can be utilized in wastewater treatment while simultaneously generating electricity.
An MFC works by anaerobically metabolizing organic matter in wastewater to release electrons and protons at the anode chamber. The protons then pass through a proton exchange membrane (PEM) and into the aerobic cathode chamber to complete a redox reaction. Electricity is then generated via electron transportation in the course of completing an electrical circuit.
There is, however, an issue with the PEM’s efficiency in channelling protons to the cathode chamber being hindered by factors such as biofouling, oxygen crossover and substrate loss.
As such, there is a need to find a membrane that is cheap, resistant to biofouling, able to prevent oxygen crossover and allow for fast, uninterrupted passage of protons into the cathode chamber.
Currently, the most commonly utilized PE in MFCs is Nafion, the brand name for a synthetic polymer with ionic properties produced by the Chemours company.
Nafion’s popularity as a PE is owed to its high proton conductivity and low internal resistance. However, its non-biodegradable nature and susceptibility to biofouling has prompted the search for alternative and innovative membranes.
A team of researchers led by Universiti Malaya’s Prof. Mohamad Suffian has found one such alternative in the form of biopolymer composites.
Comparing the composites with Nafion, the researchers found that these composites demonstrated improved proton transportation, maximum voltage potentials and power densities compared to Nafion, owing to their higher hydrophilicity (water-attraction) and water absorption.
Additionally, the biopolymer composites are conducive to creating an anaerobic environment within the anode chamber, increasing the MFC’s efficiency in treating and utilizing wastewater for electricity generation.
The research team believes that their findings will provide new avenues for biopolymers to be used in sustainable green energy production.
Sirajudeen, A.A.O., Annuar, M.S.M., Ishak, K.A., Yusuf, H., Subramaniam, R. (2021) Innovative application of biopolymer composite as proton exchange membrane in microbial fuel cell utilizing real wastewater for electricity generation. Journal of Cleaner Production, 278 (2), 123449.