KAUST catalyst promises sustainable CO2 conversion

Atmospheric CO2 is a major driver of global warming, but could also serve as a valuable resource. Many researchers are exploring ways to convert it into useful carbon-based chemicals, but efforts have been limited by low efficiencies that restrict the potential for large-scale application.

Postdoc Diego Mateo explained how the team at King Abdullah University of Science and Technology (KAUST), Saudi Arabia, based its approach on the synergistic combination of light and heat - known as the ‘photothermal effect’ - whereby heat is generated by the interaction of light with the catalyst, so the two forms of energy come from absorbed light.

The catalyst is said to be built from nickel nanoparticles on a layer of barium titanate. It captures the light in a way that kicks electrons into high energy states, known as ‘hot electrons’, researchers said. These then initiate the chemical reaction that sends CO2 back into methane.