“Like lasagna, from which the minced meat is removed and replaced with water” – A solution was found to the problem of green hydrogen production

Researchers have succeeded in developing an electrolyzer that does not use iridium as an anode material. When the new catalyst was used in the anode, it remained stable for a record 600 hours.

The study has been published in a respected journal Science -in leaf.

Hydrogen production

Current hydrogen production methods are dependent on fossil fuels and cause carbon dioxide emissions. By using cleaner sources of electricity as a power source for water electrolysis, green hydrogen can also be produced. For the production of hydrogen, so-called PEM (proton exchange membrane) electrolyzers are used.

Electrolyzers also have their own challenges. The catalyst material used in the reaction, iridium, is the rarest of all elements. It is only 0.001 ppm in the earth’s crust on average. Iridium has come to Earth mainly with meteorites.

The researchers at the Spanish institute wanted to find a suitable alternative to iridium.

Electrolysis of hydrogen takes place in highly acidic environments. With a low ph value and a high electric potential, metals tend to dissolve and no longer act as catalysts.

Iridium oxide, on the other hand, is very stable in acidic environments. This makes it the most popular metal for PEM electrolyzers.

In the past, manganese and cobalt oxides, among others, have been tried as catalysts. However, these materials did not perform satisfactorily on a significant scale.

A new solution

Researchers at the Instituto de Ciencias Fotónicas (ICFO) wanted to develop a cobalt-based catalyst because the material is abundantly available.

Previous attempts to use cobalt have failed, so the researchers chose a different approach.

“We designed a new material that incorporates the components of the reaction into its structure”, Pelayo García de Arquer,the director of the study says in a press release.

The team used a process called delamination, where part of the material was replaced with water.

“In a metaphorical way, the process can be compared to a lasagna dish, from which the minced meat is removed and replaced with water”, the researchers explain on video.

Tungsten oxide in cobalt tungsten oxide was replaced by water. This made the cobalt catalyst even more durable.

The catalyst was then used at the anode electrode during electrolysis. It was found to perform better and more stably than any previous catalysts made from cobalt.

The catalyst worked for more than 600 hours and broke previous records achieved with the material.

However, this is still far from the stability of commercially available PEM electrolyzers.

However, the results have given hope for finding a replacement for iridium.

“If necessary, we go through the entire periodic table. We are going to study and try this new structure for different substances,” says Garcia de Arquer.

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