Harnessing hydrogen production to create safe, secure and clean energy A process borrowed from natural organisms could provide Europe with masses of sustainable power. Energy © Petrmalinak, Shutterstock Europe is constantly searching for renewable energy sources and technologies. Hydrogen is a promising renewable fuel, but up till now, producing it has not been totally clean, as it relies on fossil fuels. Harnessing energy from hydrogen in a more natural way could solve these problems, presenting a clean, secure energy source to drive Europe forward into a more sustainable future. The H2Bio2Energy project explored biological methods which could solve this problem. It addressed fundamental questions on how metalloenzymes – natural enzymes that occur in many living organisms – produce hydrogen from water. This reaction naturally occurs in some microorganisms, generating H2 that can be used as a clean fuel. Yet the exact reaction mechanism is not fully understood. “The main objective of the project was to develop innovative experimental approaches that provide detailed information on the reaction mechanism. That will be essential to exploit these natural enzymes in future technologies or to design more efficient artificial catalysts,” explains Kylie Vincent, professor in inorganic chemistry at the University of Oxford, and H2Bio2Energy project coordinator. Inspiration from nature The specific type of metalloenzymes that used in the project are called [FeFe]-hydrogenases. These are found in some bacteria, and in some unicellular green algae, where they naturally produce hydrogen to support their own survival. A key factor in [FeFe]-hydrogenases is that they use iron as a catalyst, rather than platinum, as is seen elsewhere. Using iron instead of platinum for large scale industrial applications would be far easier, and cheaper, because of its wide availability on the planet. “Think about the price of a platinum ring and compare it to the price of an iron ring. The difference in cost depends on the fact that there is only a small amount of platinum in Earth’s crust, and mining it requires a lot of effort and consumes a lot of resources. On the contrary, iron is very abundant, can be easily mined and recycled,” says Simone Morra, Marie Skłodowska-Curie Research Fellow at the University of Oxford, and lead researcher on the H2Bio2Energy project. The project developed and used new innovative tools and approaches to investigate hydrogen production, all sharing the use of infrared light. This allowed the team to specifically detect what is happening at the most important part of the enzyme, the catalytic centre, which is where reactions take place. Looking forward to a clean future “Since metalloenzymes, such as [FeFe]-hydrogenases, are great at doing their job but are not usually very stable over time, our vision is that the information collected during this project will be used to copy what nature does, and produce a synthetic iron-based catalyst with excellent performances and stability,” explains Morra. This catalyst may replace platinum in the manufacturing of water electrolysers that could be used to create hydrogen used for vehicles, or in a power plant to store excess electricity (from solar panels or wind turbines). Says Morra: “This project was only made possible by the support from the Marie Skłodowska-Curie Individual Fellowship scheme, within the Horizon 2020 framework. The most positive aspect of the Fellowship is the possibility to work with any colleague you think is best for your project in Europe or the rest of the world without the limits of national borders.” Keywords H2Bio2Energy, chemistry, hydrogen, energy, green, source, enzymes
