New method of producing carbon neutral fuel from CO2

This is a new way of converting CO ₂ into a sustainable liquid fuel material that is very effective in testing and has no reaction to destroy conventional equipment.

If the idea of ​​flying a commercial battery powered airplane gets you worried, you can have a little peace of mind. The researchers have discovered a realistic starting point for converting CO ₂ into sustainable liquid fuel, including fuel for heavier vehicles that are difficult to electrify like airplanes. , passenger ships and cargo ships.

The illustration shows that the nickel electrode is like a broken old fuel pump and the cerium electrode (cerium) is like a new pump, with high productivity.(Source: Cube3D).

Carbon dioxide neutralization of CO2 is an alternative method for burying underground greenhouse gases. In a new study published today in Nature Energy , researchers from Stanford University and the Technical University of Denmark (DTU) have shown that electricity and a rich catalyst on Earth could How to convert CO2 into energy-rich CO better than conventional methods. The catalyst - cerium oxide - is much more resistant to decomposition. Separating oxygen from CO ₂ to create CO is the first step to turn CO ₂ into a form that is close to liquid and other products such as synthetic gas and plastic. The addition of hydrogen to carbon monoxide can produce fuels such as synthetic diesel and similar fuels to aircraft fuels. The team plans to use renewable energy to create carbon dioxide and its by-products, thereby creating carbon neutral products.

"We have demonstrated that we can use electricity to turn CO ₂ into CO with selectivity," said William Chueh, associate professor of materials science and engineering at Stanford, one of the three lead authors of the study. 100% without creating unwanted 'solid carbon byproducts'.

Chueh, after learning about DTU's research in this field, invited Christopher Graves, associate professor at the Energy Conversion and Storage Division of DTU and Theis Skafte, a PhD student at DTU at the time. , to Stanford and to study this technology together

Skafte, the lead author of the research and postdoctoral researcher at DTU, said: 'We have been studying CO ₂ electrolysis at high temperatures for many years, but the cooperation with Stanford University that's the key for us to achieve this breakthrough. We have achieved two inseparable things - the basic understanding and the practical presence of a material with a stronger character. "

Barriers for conversion

The advantage of sustainable liquid fuels over electrified vehicles is that we can use existing gasoline tools and facilities such as engines, pipelines and gas stations. In addition, the hurdles of electrifying aircraft and ships - long distances and large battery weights - will no longer be a problem when we use energy-efficient, neutral carbon fuels.

From left: Christopher Graves, Michal Bajdich and Michael Machala in front of the laser pulse deposition machine Machala uses to make electrodes.(Source: Mark Golden)

Although plants naturally decompose carbon dioxide into carbon-rich sugars, artificial electrochemical methods for producing carbon monoxide have not been widely commercialized. One of the problems is: Devices that use too much electricity, only convert low amounts of carbon dioxide or produce pure carbon that destroys the devices. Researchers in the new study first tested the difference between successful and failed CO ₂ electrolysis devices.

With the knowledge gained, the researchers built two fuel cells to test CO ₂ conversion: one uses cerium oxide and one uses conventional nickel catalysts. Cerium electrode remains stable, while carbon deposits damage the nickel electrode, significantly shortening the life of the catalyst.

Graves, the first author of the study and a visiting scholar at Stanford at the time, said: 'This remarkable capacity of cerium has a major impact on the actual life of electrical devices. stool CO ₂ . Replacing the existing nickel electrode with our new cerium electrode in the next generation electrolyte will improve device life. '

The road to commercialization

Eliminating the early battery drain can significantly reduce commercial CO production costs. Preventing carbon buildup also allows the new device to convert more CO2 into carbon dioxide, limiting the concentration of carbon dioxide products below 50% in current batteries. This can also help reduce production costs.

Michal Bajdich, the first author of the study and a scientific assistant at the SUNCAT Center for Interface & Catalyst Science, a collaborative achievement of the SLAC National Acceleration Laboratory and Stanford Technical School, said. : 'The mechanism of carbon inhibition on cerium is based on trapping carbon in the form of stable oxidation. We were able to explain this activity with models that calculated CO ₂ reduction at high temperatures, then confirmed by the electronic spectroscopy of the operating battery. '

The high cost of controlling CO ₂ is a barrier that makes it difficult to isolate it underground on a large scale, and this high cost can also be a barrier to using CO ₂ to generate fuel and chemistry. more sustainable substances. However, the market value of those products combined with the cost of removing carbon emissions could help technologies that use CO _{2 to} overcome the cost barrier faster.

The researchers hope that their initial study of the mechanisms that work in CO ₂ electrolysis devices by spectroscopy and modeling will help others to adjust the cerium's surface properties and properties. Other oxides to further improve CO ₂ electrolysis process.

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