A New Catalyst Rivals Platinum

Aalto University researchers in Finland have succeeded in creating an electrocatalyst made of carbon and iron used for storing electric energy by replacing platinum.

The Finns are focused on the challenge that comes with the increased use of renewable energy – how to store electric energy. Platinum has traditionally been used as the electrocatalyst in electrolysers that store electric energy as chemical compounds. But platinum is a rare and expensive metal.

The Aalto University researchers have succeeded in developing a substitute that is cheap and effective. Their findings have been published in the scientific journal Angewandte Chemie.

Senior scientist Tanja Kallio said, “We developed an electrocatalyst that is made of iron and carbon. Now the same efficiency that was achieved with platinum can be obtained with a less expensive material. Nearly 40 percent of the material costs of energy storage with an electrolyser come from the electrocatalyst.”

The manufacturing process has been developed in cooperation with a research group led by Professor Esko Kauppinen from Aalto University School of Science. The carbon nanotube the group developed conducts electricity extremely well and serves as the support, while the now added only single carbon layer covered iron functions as the catalyst. The manufacturing process has a single stage.

Iron nanoparticles are carbon-encapsulated into a single-shell that are decorated on single-walled carbon nanotubes. The constructed catalysts is introduced as a novel highly active and durable non-noble-metal catalyst for an efficient hydrogen evolution reaction.

The new catalyst exhibits catalytic properties superior to previously studied nonprecious materials and its comparable to those of platinum.

The construction is synthesized by a novel fast and low-cost aerosol chemical vapor deposition method in a one-step process. The single-shell carbon-encapsulated iron nanoparticle layer does not prevent desired access of the reactants to the vicinity of the iron nanoparticles but it does protect the active metallic core from oxidation.

Kallio noted, “The method has been altered to make the electro catalyst very active. By active, we refer to the small amount of energy needed to store electric energy as hydrogen. This reduces the losses caused by chemical storage and the process is economically viable.”

Platinum cost is a major roadblock to several technologies mostly involving catalyzing hydrogen. The Finns look to have come up with a very low cost solution if the building of the catalyst can scale up to industrial production. It looks like the iron side can scale, but there is still some progress needed for producing the carbon nanotubes.

One of these days a platinum replacement is going to break out into the market and really change the potential of fuel cells and hydrogen production.