Oct 15 2014
Researchers from China and Sweden used advanced theoretical and experimental investigations to report how a new nano-alloy made up of palladium nano-islands set in tungsten nanoparticles forms a new type of catalyst for highly effective oxygen reduction.
This is a portrait photo of Thomas Wågberg, Umea University. Credit: Mattias Pettersson
The increasing energy demand and the need for sustainable energy production necessitate a change in present-day energy systems based on fossil fuels. Researchers are working towards the development of new energy conversion and storage systems with increased efficiency, environmental compatibility and low costs.
The new nano-alloy has a palladium (Pd) to tungsten (W) ratio of 1:8 with almost the same efficiency as a pure platinum catalyst. The outstanding efficiency is due to the alloy’s distinct morphology. It is not a completely segregated two-phase system or a homogenous alloy; its morphology lies somewhere in between.
The palladium nano-islands are about 1nm in diameter and contain 10 to 20 atoms that were isolated to the surface. The distinctive environment surrounding the Pd-islands cause special effects, which when combined, convert the islands into high-efficiency catalytic hotspots for reducing oxygen.
The nanoparticles were stabilized for practical applications by anchoring them on ordered mesoporous carbon. The anchoring helps maintain the stability of the nanoparticles for a longer time period by preventing them from fusing together during fuel cell tests.
The researchers were able to create this unique material using a synthesis process, which was accomplished using just a household micro-wave oven. However, since they used argon as protective inert gas to create the unique catalyst, their experiment was conducted in a laboratory.
Wågberg and his team have been granted further funding from the Kempe Foundation to purchase a more powerful micro-wave oven in order to improve on the properties of the catalyst.