Leading solar fuels research since 1994
 

Upcoming seminars and events

 

Thursday May 23: Seminar by Paula Rodríguez-Maciá, MPI Mülheim

"Electrochemical and Spectroscopic Investigations of Energy Converting Enzymes and Bio-inspired Catalysts"

Place: The Ångström laboratory, Seminar room House 7, floor 1

Time: 15:15 - 16:00 

Abstract: 

The H2 conversion reaction has promising technological applications for the storage and recovery of energy from intermittent sources such as solar, hydroelectric and wind. To shift toward a renewable energy system, we need to develop efficient catalytic systems for the H2 conversion reaction and other important energy conversion reactions. For that, we take inspiration from natural energy converting enzymes to develop design principles which will guide the synthesis of efficient energy converting catalysts. Hydrogenases are the H2-converting catalysts in nature. These metalloenzymes use earth abundant metals such as Ni and/or Fe in their active site to reversible interconvert molecular H2 to protons and electrons in a very efficient manner. The active site of these enzymes has been a source of inspiration for the development of H2-converting molecular catalysts. Nevertheless, structural synthetic models are thought to lag behind the enzymes in terms of their performance and stability. But how do the properties of synthetic catalysts really compare to the natural enzymes? And can their properties be improved by providing the right environment? Lastly, how does the protein environment influence the properties of the active site in the natural enzymes? 

To answer these questions the [NiFe] hydrogenase from Desulfobivrio vulgaris Miyasaki F and the H2 
conversion Ni(PCy2NGly2)2 bio-inspired catalyst2 have been covalently attached to a functionalized graphite electrode using a similar strategy in both cases. In this way, we could directly compare the catalytic performance of the enzyme and the catalyst measured under exactly the same conditions.3 Similarly, the water-insoluble Ni(PCy2NPhe2)2 H2 conversion bio-inspired catalyst4 was also immobilized onto a functionalized electrode surface. Once it was surface-confined on the electrode, it maintained its catalytic activity in water showing reversible catalysis even at room temperature. Moreover, current densities and long-term stability of the Ni(PCy2NPhe2)2 complex were further improved by immobilizing it onto an electrode coated with multi-wall carbon nanotubes.

Additionally, by site-directed mutagenesis, we have altered the coordinating environment of the canonical [4Fe-4S] cluster of the active site, H-cluster, in the [FeFe] hydrogenase from the green algae Chlamydomonas reinhardtii (CrHydA1).6 All the variants were characterized by UV-Vis, EPR, FTIR and protein film voltammetry and the results are discussed on the impact of the mutation on the catalytic properties of the enzyme, with the cysteine 362 to histidine exchange showing the most dramatic effects.7 These results highlight the importance of the [4Fe-4S] cluster as the electron injection site in [FeFe] hydrogenase, modulating the redox potential and the catalytic properties of the H-cluster.

Previous news and events

CAP scientists in the TV news

At the CAP meeting in Umeå, March 4, 2019, CAP researchers were discussing future hydrogen technology. We also had the chance to test drive a fuel cell vehicle that runs on hydrogen gas. Swedish public service television filmed the event, which can be watched here: Vätgasbilar spås ha nyckelroll i framtiden


The First European Congress on Photosynthesis Research was a success!

Over 400 delegates from Europe, and all over the world, discussed recent findings in natural and artificial photosynthesison June 25 - 28, 2018. To see what it was all about, go to the conference homepage: ePS1.org

One of our prominent invited speakers, Junko Yano from Lawrence Berkeley National Laboratory, was interviewed in Swedish national radio. You can listen to the program here (mostly in Swedish).


The CAP workshop 2018

Our annual workshop was held at Sigtunahöjden in Sigtuna, on April 26-27. Thanks for all the interesting presentations everyone, you made the workshop great!

Participants on the 2018 CAP workshop in Sigtuna, basking in the April sun.

An osprey was seen flying past the workshop venue.


The Ångström laboratory (in 2010)


Last updated April 5, 2019