Nav: Home

Self-healing catalyst films for hydrogen production

May 26, 2017

Chemists at the Centre for Electrochemical Sciences at Ruhr-Universität Bochum have developed a catalyst with self-healing properties. Under the challenging conditions of water electrolysis for hydrogen production, the catalyst material regenerates itself, as long as the components required for this are present in the electrolyte solution. A team involving Stefan Barwe, Prof Dr Wolfgang Schuhmann and Dr Edgar Ventosa from the Bochum Chair of Analytical Chemistry reports on this in the journal Angewandte Chemie International Edition. The work took place as part of the cluster of excellence Resolv.

Hydrogen is considered an energy source of the future. However, finding stable and efficient catalysts to synthesise it is a challenge. This synthesis takes place using water electrolysis, with hydrogen created at one electrode and oxygen at the other. The electrodes are covered with a catalyst film, which is attacked during the reaction and becomes less effective.

Catalyst surface forms by itself

In a feasibility study, the Bochum chemists demonstrated a new way of creating a highly stable catalyst film. They added catalyst nanoparticles in the form of a powder to the solution, which surrounds the electrodes. The particles pumped through the electrode chambers collide with the electrode surface; there, a particle film forms based on electrostatic attraction forces. Particles with a positively charged surface are deposited on the anode and particles with a negatively charged surface on the cathode. The catalyst film thus forms by itself.

Via the same mechanism, the catalyst surface regenerated during the reaction. New nanoparticles from the solution moved to the electrodes, where they freshened up the worn catalyst film. This self-healing effect lasted as long as catalyst particles were present in the solution.

Stable for several days

The researchers worked with nickel electrodes. They tested two different catalyst powders for the two electrodes, one a nickel-based material and one a cobalt-based material. All of the catalyst materials formed a film a few micrometres thick on the electrodes, as electron-microscopic captures confirmed. The measurements also showed that functional systems formed that produced hydrogen in a stable manner over several days.

In further studies, the chemists now want to investigate more closely the influence of particle shape and size as well as the influence of the electrolyte solution on the efficiency and stability of the catalysts.
-end-


Ruhr-University Bochum

Related Nanoparticles Articles:

Study models new method to accelerate nanoparticles
In a new study, researchers at the University of Illinois and the Missouri University of Science and Technology modeled a method to manipulate nanoparticles as an alternative mode of propulsion for tiny spacecraft that require very small levels of thrust.
Actively swimming gold nanoparticles
Bacteria can actively move towards a nutrient source -- a phenomenon known as chemotaxis -- and they can move collectively in a process known as swarming.
Nanoparticles take a fantastic, magnetic voyage
MIT engineers have designed tiny robots that can help drug-delivery nanoparticles push their way out of the bloodstream and into a tumor or another disease site.
Quantum optical cooling of nanoparticles
One important requirement to see quantum effects is to remove all thermal energy from the particle motion, i.e. to cool it as close as possible to absolute zero temperature.
Nanoparticles help realize 'spintronic' devices
For the first time researchers have demonstrated a new way to perform functions essential to future computation three orders of magnitude faster than current commercial devices.
More Nanoparticles News and Nanoparticles Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Rethinking Anger
Anger is universal and complex: it can be quiet, festering, justified, vengeful, and destructive. This hour, TED speakers explore the many sides of anger, why we need it, and who's allowed to feel it. Guests include psychologists Ryan Martin and Russell Kolts, writer Soraya Chemaly, former talk radio host Lisa Fritsch, and business professor Dan Moshavi.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...