A team of researchers at the Molecular Electrochemistry Laboratory has developed a process capable of converting carbon dioxide (CO2) into methane (CH4) using sunlight and a molecular catalyst based on iron. This discovery represents an advance because CO2 is a particularly inert molecule rejected in mass quantities by human activities and whose impact on climate change is known. These results open a new path towards the production of solar fuel and the recycling of CO2. This work was published in the journal Nature on 17 July 2017.

Towards a production of solar fuel

Artificial photosynthesis to recycle CO2

Now considered as waste the recycling of CO2 used as a raw material is a major challenge for scientific research and a major political issue. Marc Robert and Julien Bonin have developed a process capable of converting it into methane the main component of natural gas, the third most common source of energy in the world after oil and coal.

During this process, the CO2 molecule is gradually losing its atoms of oxygen are replaced by atoms of hydrogen storing energy in the form of chemical bonds. This transformation, known as the reduction reaction makes it possible to obtain a variety of compounds ranging from carbon monoxide and formic acid (key raw materials for the chemical industry) to methanol (a liquid fuel) To methane, the most concentrated form with the most energy.

While most known processes use catalysts based on rare and valuable metals, the two researchers have developed an iron catalyst an abundant, accessible and inexpensive metal on Earth. No other molecular catalyst, had allowed this day to achieve complete reduction of CO2 CH4. This catalytic process works at ambient pressure and temperature using solar light as the only energy source, and paves the way for a circular use of CO2.

A new step towards an energy transition

By demonstrating that the combination of sunlight and an iron-based catalyst is capable of converting CO2 into a molecule with high-energy content, the Molecular Electrochemistry Laboratory shows that it is possible to store solar energy Renewable into a form of fuel compatible with existing industrial infrastructure and energy networks.