New Method Paves Way for More Efficient Renewable Energy Storage
July 21, 2014 azocleantech.com
Fang Song and Xile Hu © 2014 Alain Herzog/EPFL
Scientists at EPFL have developed a method for improving the catalysis of water-splitting reactions used for storing wind and solar energy. The method chemically peels off the outermost surface of a catalyst, thereby maximizing its active surface for the reaction.
A major challenge in renewable energy is storage. A common approach is a reaction that splits water into oxygen and hydrogen, and uses the hydrogen as a fuel to store energy. The efficiency of water splitting depends heavily on a solid substance called a catalyst. However, only the surface of the catalyst acts on the reaction, while its bulk is inactive. This restricts how much catalyst can be used, and limits the efficiency of water splitting in energy systems. Publishing in Nature Communications, EPFL scientists have developed a new method for maximizing the catalysts contribution by chemically peeling off only its active surface and excluding its bulk from the reaction. Their data, which show 2.6- to 4.5-fold increase in water-splitting efficiency, pave the way for cheaper and more efficient renewable energy storage...
...The researchers tested seven common metal oxide catalysts, including iridium oxide, which is an expensive material considered to be one of the most state-of-the-art catalysts for water splitting. Other catalysts included cheaper metal oxides based on iron, cobalt, and nickel. The data showed that exfoliated metal oxides increased the reaction rate by 2.6- to 4.5-fold compared to reactions containing the entire catalyst, meaning that if the exfoliation method is implemented in renewable energy systems, it could greatly increase energy storage. A few exfoliated cheaper catalysts even showed better efficiency than iridium oxide. The authors suggest that the enhancement of the reaction rate is mainly due to an increased number of the hotspots on the catalyst where water molecules in this case water fit and undergo reactions.
The authors state that the new method represents a top-down approach in the development of oxygen evolution reaction catalysts, with a significant impact on energy research. The relatively simple exfoliation method and the increased catalytic properties of low-cost, abundant materials can open the way for cheaper and more efficient storage of energy obtained from renewable sources...MORE>
http://www.azocleantech.com/news.aspx?newsID=20487
Great to see other countries studying ways to improve the life of humans, because the US is mired in drone research, net wiretapping, bank bailouts and the like. It could have been different but these days Hegemony trumps everything else. Disgraceful.