Many of the most pressing global challenges today and in the future center around the
scarcity of sustainable energy and water sources. The innovative microbial fuel cell
(MFC) technology addresses both as it utilizes bacteria to convert wastewaters into
electricity. Advancing this technology requires a better understanding of the optimal
materials, designs and conditions involved. The micro-sized MFC was recently
developed to serve this need by providing a rapid testing device requiring only a fraction
of the materials. Further, development of micro-liter scale MFCs has expanded into
potential applications such as remote and self-sustained power sources as well as on-chip
energy generators. By using microfabrication, the fabrication and assembly of microsized
MFCs is potentially inexpensive and mass produced.
The objective of the work within this dissertation was to explore and optimize the
micro-sized MFC to maximize power and current generation towards the goal of a usable
and application-oriented device. Micro-sized MFCs were examined and developed using
four parameters/themes considered most important in producing a high power generating,
yet usable device:
Anode- The use of nano-engineered carbon nanomaterials, carbon nanotubes and
graphene, as anode as well as testing semiconductor industry standard anode contact area
materials for enhanced current production.
Cathode- The introduction of a membrane-less air cathode to eliminate the need for
continuous chemical refills and making the entire device mobile.
Reactor design- The testing of four different reactor designs (1-75 μLs) with various
features intended to increase sustainability, cost-effectiveness, and usability of the microsized
Fuels- The utilization of real-world fuels, such as industrial wastewaters and saliva,
to power micro-sized MFCs.
The micro-sized MFC can be tailored to fit a variety of applications by varying these
parameters. The device with the highest power production here was designed to be an
inexpensive and robust power source in applications like point-of-care diagnostics in
developing countries. This 25 μL graphene nanomaterial anode, air cathode device in an
inexpensive flexible rubber architecture was powered by saliva and achieved 3.55
μW/cm2 and 35.2 W/m3. The continued optimization of MFC technology promises many
interesting and innovative applications.
|Date of Award
- Biological, Environmental Sciences and Engineering
|Muhammad Mustafa Hussain (Supervisor)
- Microbial Fuel Cell
- energy harvester