Scientist in Bio4Energy and academic partners have created a catalyst for water splitting into hydrogen and oxygen which system, if brought to scale, they say could render cost efficiency to large-scale water electrolysis systems. The intention is for these latter to be powered by electricity made from solar energy or another renewable source.
The concept could be used to produce sufficiently large amounts of hydrogen for this to be a cost-competitive energy carrier in the production of diesel or jet fuel. Springer Nature published the results last month in its Scientific Reports series.
What the researchers spread over academic institutions in Sweden, Finland and Vietnam set out to do was not necessarily to find the most productive catalyst, but rather one that was cheap, environmentally benign and—above all—performed with great stability and potential for scale up.
With work having gone on since the start of Bio4Energy’s first programme period, in 2010, they gradually perfected their idea of a catalyst comprising a three-dimensional, lightweight structure based on commercially available and cheap melamine foam and the naturally occurring metal cobalt transformed into cobalt oxide.
As in any form of water splitting, the technology involves passing an electric current through an electrode (the catalyst) to spur a reaction in which the oxygen and hydrogen atoms that make up a water molecule separate and bubble off on opposite sides of the electrode. However, as many a chemical technology researcher would have found, process problems tend to be sluggishness of the reaction and lack of stability in the system. Since hydrogen must be made in large quantities at the time for storage to be meaningful, this has meant that many an attempt at hydrogen production for transport fuel making has been discarded as being too complicated and costly.
“Hydrogen gas is difficult to store… but it is possible if you have a continuous source that produces hydrogen in large amounts and over a sufficiently large surface area. With our system, it can be produced in such amounts. The surface area needs to be large for it to be meaningful”, according to Mikkola.
“Simply put this is a system that generates oxygen and hydrogen. Pure oxygen has a lot of energy and can find many uses. Hydrogen is quite a multifaceted resource. You can burn it directly for energy. You could also use it to reduce materials, for instance in the steelmaking of the future. Today you pump hefty amounts of cox into a blast furnace [to transform iron to steel], but this spurs the formation of carbon dioxide. Instead, in principle you could add hydrogen as a reducing agent. Then there is no [direct] formation of carbon dioxide. However, the hydrogen produced today from fossilised natural gas is too expensive for it to be a viable alternative”.
The international research team behind the article Robust hierarchical 3D carbon foam electrode for efficient water electrolysis, is acknowledged as follows:
Bio4Energy Chemical Catalysis and Separation Technologies
Tung Ngoc Pham - Umeå University, Sweden and University of Danang, Vietnam
William Siljebo - Umeå University, Sweden
Krisztián Kordás - University of Oulu, Finland
Jyri-Pekka Mikkola - Umeå University, Sweden and Åbo Akademi University, Finland
Other collaboration partners
Tiva Sharifi - Umeå University, Sweden
Robin Sandström - Umeå University, Sweden
Andrey Shchukarev - Umeå University, Sweden
Thomas Wågberg - Umeå University, Sweden
University of Oulu: New, affordable and easy to upscale electrocatalyst for hydrogen production from water
Åbo Akademi University: Prof. Jyri-Pekka Mikkola at Åbo Akademi University published in Nature