CO2 Absorbed at Room Temperature by Nanotechnology
Summary - Using nanotechnology, a team of researchers led by Renu Sharma of the National Institute of Standards and Technology managed to break down CO2 into Carbon Monoxide (CO) and Oxygen (O) at room temperature. Though still fundamental and proven only in the lab, it is groundbreaking work that could pave the way for the creation of economic synthetic fuels, medicine and chemicals in a circular economy.
This article by New Scientist was translated from Dutch and added upon. For the original, click here.
Artist impression of the method that American researchers used to remove carbon dioxide by converting the molecule into carbon monoxide. Picture: NIST
The cradle of a new technological dawn?
Reducing CO2 emissions is central to the debate on how to mitigate climate change. While many scientists are looking for alternative, sustainable energy sources, some are also experimenting with chemical reactions that convert CO2 from industrial exhaust gases into another substance. Converting CO2 from exhaust gasses will lead to less of the gas ends up in the atmosphere. These types of reactions consume a lot of energy. However, a team of American scientists recently found a reaction that can take place at room temperature.
Instead of heat, they obtained the required energy using nanotechnology, in particular using aluminum nanoparticles. "In addition to reducing CO2 emissions, the technology also offers opportunities for a circular economy," says Arjan Mol, a professor of corrosion technology and electrochemistry at Delft University of Technology but not involved in this research. So why is this such a big deal then?
700 degrees Celsius separates CO2 and CO
To reduce the carbon dioxide content in industrial exhaust gases, the CO2 molecule can be converted into a carbon monoxide molecule (CO). That molecule can then be used in another chemical product. To do this, the connections in the CO2 molecule must first be broken. A lot of energy is required for this. Conventionally it takes a temperature of at least 700 degrees Celsius to subtract one of the oxygen atoms from the CO2 molecule. This makes it difficult to apply it in practice.
That's why Renu Sharma, a researcher at the National Institute of Standards and Technology, and her team decided to experiment with an alternative energy source inspired by nanotechnology.
“Carbon donor”
Sharma and colleagues used aluminum nanoparticles as a catalyst. When you irradiate it with a beam of electrons - with a diameter of 1 to 1000 nanometers - electrons of the aluminum atom in this particle start to oscillate. This provides the energy required to break open the bond in the CO2 molecule and release an oxygen atom. What is left is one CO-molecule and one “O”. To make two CO molecules out of this, an extra carbon atom (C) is needed that, as it were, clings to the free oxygen atom. That is why the reaction takes place on an extremely thin layer of graphite. "That gives off a carbon atom - like a kind of carbon donor," says Mol.
The researchers have succeeded in having this reaction take place on a small scale at room temperature. "And with that they have done groundbreaking fundamental work," says Mol.
Circular and synthetic fuels, medicine and other chemicals
The CO molecules that are released during this process are poisonous. But if you add hydrogen to the factory chimney, you could produce methane or ethanol. In other words: synthetic fuel. These substances can then be easily processed into commonly used products such as medicines, cleaning products and cosmetics. "In this way, this study not only contributes to reducing carbon emissions, but also to the circular challenge," says Mol.
Unfortunately, the method has not yet been applied to real industrial processes. The researchers conducted the experiment in a controlled environment with dimensions of just a few nanometers. "Before the researchers can apply the technique on a large scale, we still have to answer many questions," says Mol. "But that makes sense; this is how new breakthroughs begin. We are at the cradle of an innovative and promising technique. "