A microbial fuel cell (MFC) or biological fuel
cell electrochemical system drives an electric current by
using bacteria found in nature. MFC’s can be grouped
into two general categories i.e. mediated MFC and
unmediated MFC. There are two chambers in the fuel
cell i.e. the anodic chamber and the cathodic chamber.
Both the electrodes are immersed in the respective
chamber for the flow of electrons. Moreover, a salt
bridge can be set-up in between the chambers for the
flow of protons or a proton exchange membrane (PEM)
can also be used. Various types of electrodes can be
used according to the requirement. The pencil lead type
graphite electrode provides more surface area which
results in higher voltages as compared to wire mesh
type carbon paper electrodes. Performing different
trials for different types of water, electrodes and NaCl
concentration an appropriate result can be concluded.
By comparing the time and voltages data of trials on a
graph, the economical and feasible trial can be selected.
The fuel cells can be used for various applications like
waste water treatment, generation of current using
organic waste as well as can be used as bio-sensors for
the determination of Biochemical Oxygen Demand
(BOD). The advantages of MFC’s are many but its use
for production of electric current from waste is driving
people’s attention. Humanity has just touched the
surface of MFC’s and there is a vast scope of future
Keywords : MFC, Mediated and Unmediated, Salt Bridge, Electric Current, Applications.