Fast and sustainable method for hydrogen production

A German-Chinese research team has developed a new method for the electrochemical splitting of water. This will not only accelerate the production of hydrogen for technology and industry, but also make it more sustainable, as the researchers report in Nature Nanotechnology.

Due to its unique properties, hydrogen is of crucial importance for technology and industry: it is the lightest chemical element, has an enormously high energy density and is an emission-free fuel, as it only produces water as a by-product during combustion. This makes hydrogen an extremely attractive clean energy source. However, its production is still extremely energy-intensive. Hydrogen can be produced via a process of electrochemical splitting which energises the electrodes in water. The energy-saving and efficient production of hydrogen by way of electrochemical water splitting using renewable electricity can significantly improve the sustainability of this energy source.

Oxygen evolution reaction - a big challenge 

One of the biggest challenges in electrochemical water splitting is the so-called oxygen evolution reaction (OER), an inert reaction in which the water molecules are broken down into their individual components – oxygen and hydrogen – as the University of Bayreuth mentions in a recent press release. The OER can be accelerated by using certain precious metals, but the metals are rare and therefore expensive, and accelerating the reaction costs additional energy (overvoltage). A research team consisting of members from various Chinese research institutions and led by Professor Francesco Ciucci of the Chair of Electrode Design for Electrochemical Energy Systems at the University of Bayreuth has tackled this problem. It developed an innovative method of electrochemical water splitting in which individual atoms of the precious metal iridium are coupled as reaction accelerators with dimethylimidazole and cobalt iron hydroxide. The main innovation lies in the geometric arrangement of the components: the coupled components of this iridium compound are not on the same level, but are instead geometrically distributed in order to optimise performance and efficiency.

Extremely low overvoltage

This innovative approach significantly increases OER activity and also has an extremely low overvoltage. It also reduces the amount of precious metal consumed as it uses only individual iridium atoms and has a positive effect on the stability of the acceleration reaction.
“Our study represents a significant step forward in the development of efficient, cost-effective OER acceleration for sustainable hydrogen production. By overcoming the key problem of current technology, our findings have the potential to drive the global transition to clean energy solutions”, says Ciucci, who is the last author of the study.
Source: idw/Uni Bayreuth