By Will Soutter
A new fuel cell catalyst made from gelatin has been created at Birmingham University. The material could replace the much more expensive platinum in fuel cells for vehicles and small-scale electricity generation.
Gelatin could hold the key to green synthesis of fuel cell catalysts. Image credit: Photos.com
A research team led by Dr Zoe Schnepp used gelatin, an animal protein obtained from bones, skin, tendons and other unused parts of the animal in the food industry, which is used to make many food products, cosmetics, and some pharmaceuticals.
The researchers found that adding iron and magnesium nitrates to the gelatin causes it to foam up into a sponge structure.
The metal salts also became bound into the biomass, in the form of magnesium oxide and iron carbide nanoparticles.
When these nanoparticles were washed away, they left behind a complex structure of pores with a wide range of sizes, from relatively large 100-micron bubbles in the initial foam all the way down to nanopores left behind by the iron carbide particles.
This complex porous structure is ideal for fuel cell applications, as it allows the gaseous fuel and oxygen to flow freely. The material showed good catalytic activity for the oxygen reduction reaction, which is crucial for fuel cells.
Whilst the gelatin-based material can't quite beat platinum or other expensive metals on performance, it is significantly cheaper. This may help to overcome the cost barriers associated with widespread commercial adoption of fuel cell technology.
This research could also provide a pathway to further discoveries. Schnepp's team have developed a cost-effective, single-step method to create iron carbide nanoparticles supported in a porous network.
Metal carbides are being investigated more and more as replacements for noble metal catalysts, so this new method could have wider reaching implications across the whole chemical industry.