Researchers at the Institut de Recerca Química de Catalunya (ICIQ) have managed for the first time to increase the production of hydrogen in the water division reaction with the help of a magnet. The simplicity of the discovery opens new opportunities to implement the use of magnetic fields during this process.
Magnetism can be key to boosting the hydrogen economy
The formation of hydrogen bubbles increases as the magnet approaches the anode.
The need to find a sustainable alternative to CO2-producing fuels is pressing, and one of the options is to resort to hydrogen generated by the separation of water, the reaction in which water breaks down into oxygen and hydrogen. Now, researchers at the Institut de Recerca Química de Catalunya may have found the key to approaching this hydrogen economy in an unexpected way.
In an article published in Nature Energy, ICIQ scientists describe how, for the first time, a magnet has been used to directly improve hydrogen production in alkaline water divided by electrolysis. “The simplicity of the discovery opens new opportunities to implement magnetic improvement in water division. In addition, the low cost of the technology makes it suitable for industrial applications,” explains Felipe A. Garcés-Pineda, first author of the article.
The research shows how the presence of an external and induced magnetic field by bringing a neodymium magnet closer to the electrolyzer stimulates electrocatalytic activity at the anode, in some cases doubling hydrogen production. The scientists indicate that the magnetic field directly affects the reaction pathway by allowing the preservation of the active catalyst spin, which in turn favors the parallel spin alignment of the oxygen atoms during the reaction.
This general spin polarization, due to the external magnetic field, improves the efficiency of the process. “This shows that there is much to learn from the intimate reaction mechanisms that take place in electrocatalysts and opens up new ways to overcome the limitations of state-of-the-art systems,” says Núria López, co-author of the article published in Nature Energy.
The best catalyst
The researchers studied a variety of catalysts under identical working conditions and reported that the improvement in catalytic activity is proportional to the magnetic nature of the catalysts used to conduct the water division reaction. Thus they proved that the highly magnetic NiZnFe4Ox ferrite exhibited the greatest improvement effect when presented with a magnetic field. This ferrite also has the advantage of being magnetically attached to a nickel metal support, which reduces the need to use binders to attach catalysts to a physical support.
Leading the Catalan centre project is José Ramón Galán-Mascarós, who participates in CREATE and A-LEAF, two European projects dedicated to reducing the production costs of hydrogen and other clean fuels. Both European consortia are working to develop platforms to produce renewable fuels without using critical raw materials.
For the scientist, finding technological solutions that avoid the use of noble metals, such as platinum or iridium, is the real challenge. It is also a prerequisite for making the hydrogen energy cycle viable: as noble metals are expensive and extremely scarce, their use limits the expansion of mass production technologies. Instead, scientists are looking for alternatives that are abundant on land, capable of offering very good performance under alkaline conditions, and allow for an economically viable scale.
The challenge of making sustainable fuels widely available requires a multidisciplinary effort and, ultimately, international collaboration,” concludes Galán Mascarós.