TUM – Technical University of Munich Menu
Eine Kupferschicht unter der Oberfläche verleiht dem Platin-Katalysator eine deutlich höhere Aktivität und eine längere Lebensdauer – Bild: Federico Calle Vallejo / Univ. Leiden
Eine Kupferschicht unter der Oberfläche verleiht dem Platin-Katalysator eine deutlich höhere Aktivität und eine längere Lebensdauer – Bild: Federico Calle Vallejo / Univ. Leiden
  • Research news

A sub-surface copper layer boosts activity of platinum electrodes

Efficiency of water electrolysis doubled

Water electrolysis has not yet established itself as a method for the production of hydrogen. Too much energy is lost in the process. With a trick researchers of the Technical University of Munich (TUM), the Ruhr University Bochum and Leiden University have now doubled the efficiency of the reaction.

Yet wind turbines have to be switched off when there is too much energy in the grid. Alternatively excess energy could drive the splitting of water into hydrogen and oxygen. But so far, hydrogen is industrially produced mainly from natural gas, although this releases large amounts of the greenhouse gas carbon dioxide. But the process is still cheaper than the electrolysis of water.

Typically, platinum is applied as catalyst, in order to accelerate the conversion of water to hydrogen and oxygen. For the reaction to be as efficient as possible, intermediates must not adhere too strongly or too weakly at the catalyst surface.

Traditional electrodes bind intermediates too strongly

The team headed by Prof. Aliaksandr Bandarenka from the Department of Physics of Energy Conversion and Storage at TUM and Prof. Wolfgang Schuhmann from the Center for Electrochemical Sciences in Bochum now calculated how strongly intermediates must adhere to the electrodes, in order to most efficiently facilitate the reaction. The analysis revealed that traditional electrodes from platinum, rhodium and palladium bind the intermediates a bit too strongly.

Thus the researchers modified the properties of the platinum catalyst surface by applying a layer of copper atoms. With this additional layer, the system generated twice the amount of hydrogen than with a pure platinum electrode. But only if the researchers applied the copper layer directly under the top layer of the platinum atoms. The group observed another useful side effect: the copper layer extended the service life of the electrodes, for example by rendering them more corrosion-resistant.

Water electrolysis could be powered by surplus electricity

Only four per cent of all hydrogen produced worldwide are the result of water electrolysis. As the electrodes used in the process are not efficient enough, large-scale application is not profitable. “To date, hydrogen has been mainly obtained from fossil fuels, with large CO2 volumes being released in the process,” says Wolfgang Schuhmann. “If we succeeded in obtaining hydrogen by using electrolysis instead, it would be a huge step towards climate-friendly energy conversion. For this purpose, we could utilise surplus electricity, for example generated by wind power.”

“In addition, the research on this reaction allows us to test, how well we can design catalyst surfaces by precisely positioning different metal atoms,“ adds Aliaksandr Bandarenka. „A knowledge many other catalytic processes might benefit from.”

The German Research Foundation has financed the project under the umbrella of the Clusters of Excellence RESOLV and Nanosystems Initiative Munich (NIM). Additional funding was supplied by the Helmholtz-Energy-Alliance “Stationary electrochemical storage systems and converters”.

Publication:

J. Tymoczko, F. Calle-Vallejo, W. Schuhmann, A. S. Bandarenka: Making the hydrogen evolution reaction in polymer electrolyte membrane electrolyzers even faster; Nature Communications, 10.03.2016 – DOI: 10.1038/NCOMMS10990

Contact:

Prof. Dr. Aliaksandr S. Bandarenka
Technical University of Munich
Physics of Energy Conversion and Storage
James-Franck-Str. 1, 85748 Garching, Germany
Tel.: +49 89 289 12531E-MailWeb

Corporate Communications Center

Technical University of Munich

Article at tum.de

The first authors of the project in their laboratory at the Catalysis Research Center (CRC) of TUM: Dr. Batyr Garlyyev, Kathrin Kratzl and Marlon Rück (f.l.t.r.)

Activity of fuel cell catalysts doubled

An interdisciplinary research team at the Technical University of Munich (TUM) has built platinum nanoparticles for catalysis in fuel cells: The new size-optimized catalysts are twice as good as the best process...

Windräder, Solarmodule und Wasserstoffspeicher

How power-to-gas technology can be green and profitable

Hydrogen production based on wind power can already be commercially viable today. Until now, it was generally assumed that this environmentally friendly power-to-gas technology could not be implemented profitably....

Jonas Pfisterer und Yunchang Liang am Rastertunnel-Mikroskop im Labor der Arbeitsgruppe von Prof. Bandarenka, Professur für Physik der Energiewandlung und -speicherung der TU München. (Bild: Wenzel Schürmann / TUM)

Chemical hotspots

Chemistry live: Using a scanning tunneling microscope, researchers at the Technical University of Munich (TUM) were able for the very first time to witness in detail the activity of catalysts during an electro-chemical...

Das Zentralinstitut für Katalyseforschung der TUM, Ostansicht - Bild: Andreas Heddergott / TUM

TUM opens central institute for catalysis research

With the inauguration of the TUM Catalysis Research Center (CRC), the Technical University of Munich (TUM) sets an international highlight in the field of catalysis research. Scientists from five departments, as well as...

Andrew Crampton und Marian Rötzer an ihrer Vakuum-Anlage zur Herstellung ultrakleiner Katalysatorpartikel - Foto: Andreas Heddergott / TUM

Small is different

In the production of margarine millions of tons of unsaturated fatty acids are converted from vegetable oils using hydrogen. While searching for improved catalysts for these so-called hydrogenation reactions, a...

Die unterschiedliche Zahl gleichartiger Nachbarn hat einen wichtigen Einfluss auf die katalytische Aktivität von Oberflächenatomen eines Nanopartikels – Bild: David Loffreda, CNRS, Lyon

Faster design – better catalysts

While the cleaning of car exhausts is among the best known applications of catalytic processes, it is only the tip of the iceberg. Practically the entire chemical industry relies on catalytic reactions. Catalyst design...

Kobalthaltiger Katalysator zur Umwandlung von Kohlendioxid in Methan – Bild: Andreas Battenberg / TUM

Climate killer as a climate rescuer

When clouds cloak the sun, the production of solar power drops abruptly. When the wind lulls, wind parks quit producing energy. On the other hand, there are days on which wind power stations must be shut down because there...