Proton Exchange Membrane Fuel Cells (PEMFCs) provide
electricity by using hydrogen as fuel and expelling heat and water as exhaust.
PEMFCs are the promising power sources for automotive, stationary and mobile
electronics because of their higher power densities and environmental benefits
and hence they have attracted enormous interest. Unfortunately, for wide-scale
commercialization, this technology must overcome several challenges including
three critical barriers: performance, cost and durability. Platinum is
frequently used in PEMFCs because it is a highly effective catalyst, however,
platinum is expensive – and the loading efficiency is too low to offer cost
efficient electrochemically active surface area. The common membrane electrode
assemblies for PEMFCs are unstable, resulting in poor durability. The solution
to these problems is to increase cost-efficiency by increasing the
electrochemically active surface area of the platinum, as well as increase the
durability of the electrodes.
Researchers at Arizona State University (ASU) have narrowed
down the particle size and evenly distributed the platinum by using Multi-Walled
Carbon Nanotubes (MWCNTs). MWCNTs are well known to have extremely high surface
area, and very high durability. Combining platinum with MWCNTs has resulted in
high power output with a low amount of platinum used. The combined
platinum-MWCNT catalyst has also shown significantly high performance and
exceptional durability.
Potential Applications
- Vehicles
- Portable electronic devices
- Satellites
- Emergency power systems
Benefits and Advantages
- Platinum cost savings of 30% are achievable.
- 25% improvement in fuel cell power density
- Improved lifetime and durability
- Carbon nanotubes are commercially available in a
competitive and growing market.