Hydrogenation of CO2 with ten times less cobalt
The transition to a carbon-neutral economy will depend on cheap and abundant renewable energy as well as on technologies that can store this energy for later use. Storing surplus energy in chemical bonds is effective. One approach is to convert CO2 to hydrocarbons with the help of H2 obtained by electrolysis. The most simple hydrocarbon, methane (CH4) is a fuel that can be readily used for heating. This can be done by catalysts that often require expensive metals such as cobalt.
Breakthrough in catalysis
Research work by TU/e, together with an international team of collaborators, constitutes a breakthrough in catalysis. It shows that for many essential reactions relevant to sustainable chemistry, it is possible to design catalysts that use much less of such scarce metals.
Demand for cobalt expected to outstrip supply
Cobalt is an expensive metal, which is mined in a limited number of countries and is used for many applications related to sustainability such as batteries. As these are growing markets, the demand is foreseen to outstrip supply in the energy transition, leading to even higher prices.
Although this work is proof of principle, the researchers showed that catalysts containing much less expensive cobalt can operate in a stable manner under near-industrial conditions. This means a major step forward for the manufacture of so-called e-fuels, which are hydrocarbons manufactured from air-captured CO2 and H2 from water electrolysis.
This technology can also be used to obtain other hydrocarbons such as those used by airplanes. As such, this technology also brings sustainable aviation fuels one step closer to practice.
Retaining catalytic reaction power
So far, the best catalysts used for storing H2 with CO2 in hydrocarbons should contain nanoparticles with a diameter of at least 6 nm. These particles contain thousands of cobalt atoms of which less than 15% are actually used to actually help make hydrocarbons. The researchers found a way to stabilize very small clusters of a few cobalt atoms so that the cobalt efficiency is much higher: with ten times less cobalt, they can make catalysts that are even better than conventional ones.
Source: TU/e