Chemistry and the energy challenges of the ^21st century : from the sun to new energies

The conversion of solar energy into fuel is in fact admirably achieved by the living world, which constantly uses the sun to transform water and carbon dioxide into the high-energy molecules found in biomass. The field of biofuels will be discussed by G. Peltier. Some living organisms even have the capacity to perform a simple photolysis of water: they use solar energy to transform water into oxygen and hydrogen, a real tour de force when we know that water does not absorb photons from the sun and that the processes involved in this photolysis are highly complex multi-electronic processes. To achieve this, these microorganisms have developed incredibly sophisticated and efficient enzymatic systems for collecting light photons, translating this light absorption into chemical energy and catalyzing electron transfer reactions. What's remarkable is that these systems have managed to use only very abundant metals, whereas the most efficient electrolyzer or battery devices developed by chemists and used today require noble metals such as platinum, which are very expensive and scarce in the earth's crust. We often forget to mention that there's no future for a hydrogen economy if we don't solve these catalyst problems. For example, for the reduction of water to hydrogen or for the reverse reaction, hydrogenases use nickel or iron. Enzymes are therefore a fascinating source of inspiration for chemists, who dream of "copying" the living and inventing new catalysts that reproduce some of the remarkable structural and functional properties of enzyme active sites. This is known as bio-inspired chemistry. This will be illustrated by a seminar given by F. Gloaguen.

Finally, a lesson will be given on the question of carbon dioxide recovery using molecular chemistry and biocatalysis approaches.