Convert CO2 into Raw Materials Using Nanoparticles

(Ruhr University Bochum (Google Translation)) Enzymes use cascade reactions to produce complex molecules from comparatively simple raw materials. The principle was copied by researchers. An international research team has converted carbon dioxide into raw materials using nanoparticles. The scientists at the Ruhr University Bochum and the University of New South Wales in Australia looked at the principle for this from enzymes that produce complex molecules in many-step reactions. The team transferred this mechanism to metallic nanoparticles, also called nanozymes. For example, chemists created carbon dioxide from ethanol and propanol, which are common feedstocks for the chemical industry.

The team around Prof. Dr. med. Wolfgang Schuhmann from the Bochum Center for Electrochemistry and Prof. Dr. med. Corina Andronescu from the University of Duisburg-Essen reports together with the Australian team around Prof. Dr. med. Justin Gooding and Prof. dr. Richard Tilley in the Journal of the American Chemical Society of August 25, 2019.

"Transferring the cascade reactions of the enzymes to catalytically active nanoparticles could be a decisive step in the design of catalysts," says Wolfgang Schuhmann.

Particles with two active centers

Enzymes have several active sites for cascade reactions that specialize in specific reaction steps. Thus, a single enzyme can produce a complex product from a comparatively simple starting material. To mimic this concept, the researchers synthesized a particle with a silver core surrounded by a porous layer of copper. The silver core serves as the first active center, the copper layer as the second. Intermediates formed in the silver core then react in the copper layer to form more complex molecules that ultimately leave the particle.

In the present work, the German-Australian team showed that the electrochemical reduction of carbon dioxide can take place in nanozymes. Several reaction steps on the silver core and copper shell transform the starting material to ethanol or propanol.

"There are other nanoparticles that can produce these products from CO ₂ without a cascade principle ," says Wolfgang Schuhmann. "However, they need significantly more energy."

The researchers now want to further develop the concept of the cascade reaction in nanoparticles in order to be able to selectively produce even more valuable products such as ethylene or butanol. READ MORE