Workplan and work packages.
The idea and vision behind the science in SOLAR-H.
Our idea is to use principles from Nature's photosynthesis to convert solar energy to chemical energy. Our approach is original, novel and integrates, for the first time on a European scale, natural and artificial photosynthesis: living photosynthetic organisms in bioreactors and man-made photosynthetic chemical complexes in technical devices.
Our aim is to develop the a research network to enable interactive and integrated research aimed at the formation of H2 - with water as raw material and solar energy as the energy source. We will explore and develop both natural and artificial photosynthesis to achieve this goal . In both natural and artificial photosynthesis, solar energy is used to split water (photo-oxidize water) to electrons, protons and oxygen according to:
In natural photosynthesis the electrons are normally used to form energy-rich products like carbohydrates but may be diverted by the organism to produce hydrogen under certain circumstances. In artificial photosynthesis however, the electrons can be directly used to catalyze hydrogen formation.
In both systems the overall reaction to form hydrogen is that the electrons derived from water are reacted with protons according to:
that is an environmentally friendly fuel giving rise to water upon use
(2H2 +O2 → 2H2O).
Graphical presentation of work packages.
There are four scientific work packages where the science is defined (Work packages 1-4). These are connected to each other according to Fig 1. There are 3 other work packages that deal with dissemination of results (work package 5); work shops (work package 6) and coordination/management/integration (work package 7).
Work package 1. Photochemical water splitting. Design, synthesis and characterization of large bio-mimetic catalysts.
Work package 2. Bio-molecular foundation for photochemical water-splitting and photo-biological hydrogen formation.
Work package 3. Genetic and metabolic foundation for "improvement" of microorganisms for photo-biological hydrogen production.
Work package 4. Photo-biological hydrogen production. Development and demonstration of bioreactors.
Figure 1. The work packages in SOLAR-H. The figure shows how we integrate research in many fields to achieve two types of hydrogen production from solar energy and water during the development of SOLAR-H. Feedback between work packages 2 and 3 creates an interactive atmosphere and generates input of the latest knowledge from each work package into the other. The link between work packages 1 and 4 where we attempt hydrogen formation in two distinct manners is made out from research in work packages 2 and 3 where knowledge transfer is a core activity and an important part of the work.
Work Package 1- Photochemical water splitting. Design, synthesis and characterization of large bio-mimetic catalysts. Design and synthesis of bio-mimetic complexes.
This is one corner stone of SOLAR-H where we have assembled synthetic groups in the field of Mn chemistry mimicking the water splitting complex in Photosystem II. Partners 3 and 4 started their work almost 15 years ago. At that time the target was to synthesize Mn-complexes that could be used a spectroscopic models for the natural Mn-cluster - and important contributions were and are made by both groups (as recent example, Partner 4 has published (2002 and 2005) studies where a synthetic complex was used to mimic the complex interactions in the Manganese-Tyrosine ensemble in Photosystem II). The bio-mimetic chemistry now incorporates a higher level of complexity. This is connected to the advances in the field of Photosystem II research, and Partner 1 and their Swedish colleagues have accomplished the most advanced systems, permitting light-driven 4-step oxidation of the Mn-moiety.
In this work package, SOLAR-H has also collected synthetic groups that attempt to couple a catalytically active Fe-Fe or Fe-Ni complex to a photoactive Ru-center. Partners 3, 4 and 1 pursue this work.
Work Package 2. The bio-molecular foundation for photochemical water-splitting and photo-biological hydrogen formation.
The bio-mimetic synthetic chemistry is dependent on a sophisticated level of knowledge and detailed understanding of the natural systems. It is necessary that the latest advances in biochemistry and biophysics are rapidly evaluated and translated into chemical design and synthesis of the bio-mimetic molecules. This linking is the prerequisite for any success in our complex research. Therefore SOLAR-H incorporates partners at the international forefront of biochemical and biophysical investigations of both hydrogenases and the water oxidizing Mn-tyrosine complex in Photosystem II. Several hydrogenases from different sources have recently been structurally determined and these structures have led to novel design principles for the synthetic hydrogenase mimics that are targets for Partners 1 and 3. In addition, the detailed knowledge has allowed high-level spectroscopy of the chemical mechanism of hydrogenases and SOLAR-H involves state-of the art spectroscopy in this system (Partner 4). In addition, partner 2A, a leading bio-spectroscopy group famous world-wide for its contribution to photosynthetic electron transfer, has initiated an ambitious program to study photo-driven hydrogenase and its models under the auspices of national programs in France.
SOLAR-H has adopted the same strategy for our studies of photosynthetic water-splitting. In Nature water splitting is only achieved by the Mn-Tyrosine ensemble in Photosystem II. The cyclic mechanism of this complicated redox system is studied by Partners 1 and 2A. Both groups apply EPR spectroscopy to the many redox states acquired by the Mn-cluster and are well-known international groups in this competitive field. They also interact closely with the Ru-Mn synthesizing partners (1 within the Swedish Consortium and Partner 2A with Partner 3 in France).
Work package 3. The genetic and metabolic foundation for "improvement" of microorganisms for photobiological hydrogen production.
The critical point in the second leg in SOLAR-H is to identify, characterize, modify and then further develop suitable photosynthetic microorganisms able to convert solar energy and water into chemical energy in the form of H2. SOLAR-H incorporates a large body of European expertise in both cyanobacteria (for example Nostoc and Anabena sp.) and green algae (for example Chlamydomonas). Partners 1 (Lindblad) and 5 develop the molecular biology aimed at hydrogen formation in cyanobacteria and they were, e.g., the first to eliminate the natural hydrogenase in Nostoc sp. Partner 5 was also the first to clone the hydrogenase gene in Chlamydomonas. SOLAR-H also involves Partner 8, who studies the molecular regulation of photosynthesis and genes related to photosynthesis in Chlamydomonas and other green algae.
In addition, significant interest and resources will be allocated to increase the photosynthetic efficiencies. This effort also includes Partner 2C. This laboratory is specialized in understanding how light and other environmental stress conditions regulates the entire metabolism in photosynthetic microorganisms, and it is especially focused on problems related to the release of different gaseous products (in particular H2) from green algae. SOLAR-H also incorporates genetic knowledge about other microbial hydrogenases through Partner 6. Here the knowledge is higher than in photosynthetic microorganisms (the field is much more developed), so the competence brought to SOLAR-H by Partner 6 is necessary to be able to control genetically the hydrogenase expression and regulation in the photosynthetic microorganisms.
Work package 4. Photobiological hydrogen production. Development and demonstration of bioreactors.
One purpose of SOLAR-H is to demonstrate efficient photobiological hydrogen production both from cyanobacteria and green algae in bio-reactors - in essence renewable H2 produced from sun and water. The use of photosynthetic microorganisms brings new problems and challenges to the bioreactor groups, and Partner 7 has a large technological laboratory for bioreactor design and development. In particular their competence to work with photo-bioreactors (where light is the most important and often limiting factor), is of central importance to SOLAR-H. Smaller bioreactors for lab-scale use are also developed by Partners 1 and 5 in order to test present (and obtained) microorganisms.
Work package 5. Dissemination of results.
This work package deals with publication of results and the SOLAR-H homepage.
This work package is lead by the conference manager and deals with our scientific discussion meetings.
Work package 7.Coordination/managment/integration.
This work package deals with the coordination and management of SOLAR-H.