The environment of the catalytic site acts as a reservoir within a hydrogen-producing enzyme, making the production of hydrogen for renewable energy much more efficient. This is the conclusion scientists at the Max Planck Institute for Chemical Energy Conversion (MPI CEC) and the Ruhr-Universität Bochum (RUB) reached through a detailed spectroscopic investigation published in the journal Angewandte Chemie.
This enzyme has a double-iron core and an iron-sulphur cluster in the periphery, and it is also known as hydrogenases. It acts as a catalyst in the process of conversion and formation of hydrogen, making it very popular in the field of green energy research.
The team demonstrated that during hydrogen production (when two electrons pair up with two protons), the first electron is transferred to the iron centre of the enzyme, while the second is sent to the iron-sulfur cluster and therefore stored. Later on, both electrons are moved together to the protons by the enzyme to form hydrogen.
The spectroscopic techniques were applied by the doctoral student Agnieszka Adamska, also a lead author of the publication, who states that this type of analysis was the only way to explain hydrogenases. According to Camilla Lambertz, a postdoc at the same institute, tens of thousands of hydrogen molecules can be produced per second by one iron centre. This classifies the enzyme as one of the most efficient hydrogenases.
However, the team at at MPI CEC and the Ruhr-Universität Bochum is not completely finished with their experiments. They now want to use different spectroscopic methods in order to locate the protons and use this knowledge to develop their own hydrogen-producing catalyst.