Electrolysis rate doubled

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Professor Alexander Bondarenko and Yakub Timoshko from the Ruhr University (Germany) with colleagues from the Technical University of Munich and the University of Leiden found a way to double the efficiency of electrolysis. The catalyst they created is made of platinum, as usual, but with a layer of copper atoms. It turned out that the modified catalyst releases two times more hydrogen from water than a conventional platinum catalyst without a copper coating.

Water electrolysis is a well-known process of splitting water into hydrogen and oxygen. It is still not used on an industrial scale, because it requires too much energy, that is, it is unprofitable by itself. Today, only 4% of hydrogen in the world is produced using electrolysis.

Physicists are looking for different ways to improve the energy efficiency of electrolysis, for example, using new materials and even using solar energy (photolysis, see the article “ Water splitting with an efficiency of 100%: half the battle is done ”). Twice the increase in efficiency of the standard catalyst is a very important achievement.
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The efficiency of electrolysis depends on how long the intermediate reaction products linger on the surface of the catalyst. The authors of the research found that they linger on standard catalysts of platinum, rhodium and palladium for too long, and if this bond is weakened, the efficiency of the reaction increases with the same energy consumption. They changed the properties of the platinum catalyst by depositing a layer of copper atoms on it.

But there is one trick: the effect appears if a layer of copper atoms is applied under the top layer of platinum atoms, and not on top of it.


Voltammograms for different types of platinum and copper catalysts in HClO ₄



In addition to doubling the efficiency, a side effect also manifested itself: such catalysts are more resistant to corrosion and last longer.

“Nowadays, hydrogen is mainly extracted from fossil fuels, with a large amount of CO _{2 released} ,” said Wolfgang Schuhmann, co-author of the research. If we can instead produce hydrogen by electrolysis, this will be a giant step towards environmentally friendly energy conversion. For example, we could recycle surplus electricity from wind stations. ”

“In addition, the study of this reaction allows us to study how well we can design catalytic surfaces by precisely placing atoms of various metals,” added Professor Bondarenko. “This knowledge is useful in other catalytic processes.”

The scientific article was published on March 10 in the journal Nature Communications (doi: 10.1038 / ncomms10990).