Turning CO2 and methane into valuable products, effectively by preventing catalyst poisoning

CO2 and methane can be turned into valuable products. But there is a problem with the catalysts required for this: They end up being covered in a layer of carbon, losing their effectivity. Researchers at Vienna University of Technology have now created a catalyst with fundamentally different properties: They have used perovskites, which are crystals containing oxygen, which can be doped with various metal atoms, inserted, such as nickel or cobalt, into the perovskite -- metals that have also been used in catalysis before. special pre-treatment of the crystal with hydrogen at around 600 °C allows the nickel or cobalt atoms to migrate to the surface and form nanoparticles there. The size of the nanoparticles is crucial: Success has been achieved with nanoparticles with a diameter of 30 to 50 nanometres. The desired chemical reaction then takes place on these tiny grains, but at the same time the oxygen contained in the perovskite prevents the formation of carbon nanotubes.



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