a cheap metal that can produce 1000% more hydrogen

Green hydrogen, which is produced using renewable energy through the electrolysis of water, is a big potential for the energy sector. Countries such as Spain are entrusting their future to this energy vector, but more research is needed to make its production sustainable. And this is where Japan has an advantage.

A little context. In recent years, PEM electrolysers, which use a proton exchange membrane as the electrolyte, have become increasingly popular in hydrogen production due to their higher efficiency and ability to respond quickly to intermittent energy sources.

The problem with PEM-type electrolyzers is that they are more expensive. They need efficient catalysts that are resistant to acid corrosion, so they use platinum or iridium, rare and expensive metals.

Looking for a cheap catalyst. Iridium catalysts support the oxygen evolution reaction longer and allow larger volumes of hydrogen to be produced. Is there a cheap material that can do the same?

Researchers at the RIKEN Institute in Japan started with a common metal, manganese, and modified its three-dimensional structure to create the first efficient and durable PEM electrolyzer without rare metals.

The secret is in its three-dimensional structure. The researchers developed a manganese oxide (MnO2) catalyst by manipulating the material’s lattice structure so that it forms stronger bonds with oxygen atoms.

Improved MnO2 is much more stable than other base metal catalysts and maintains its reaction with water much longer.

1000% more hydrogen. According to a study published in the journal Nature Catalysis, MnO2 increases the life of other cheap catalysts by 40 times. The material is more resistant to dissolution in acid and is more stable during the reaction.

In laboratory tests, the catalyst operated for over a thousand hours at 200 mA/cm², producing 10 times more hydrogen than other materials.

This is just the beginning. There is still work to be done to use the new material in industrial electrolysers, but the researchers believe the discovery will play a critical role in sustainable hydrogen production.

Future modifications to the manganese structure could further increase the current density supported by the material and the life of the catalyst, with the long-term goal of making iridium-free water electrolysis possible.

Image | RIKEN Center for Sustainable Resources Research

In Hatak | If green hydrogen wants to get cheaper and succeed, you already know what it can do: use fewer rare metals.