Chemists design novel method for generating sustainable fuel

Chemists have long been working to synthesize high-value materials from waste molecules, and now an international collaboration of scientists is exploring how to use electricity to make the process more efficient.

In their research, Published in Natural CatalystThe researchers: carbon dioxide, Greenhouse gasescan be converted into a type of liquid fuel. methanol In a very efficient way.

The process was achieved by uniformly coating cobalt phthalocyanine (CoPc) molecules onto carbon nanotubes (graphene-like tubes with unique electrical properties) on their surfaces in an electrolyte solution. Current This allowed the CoPc molecule to receive electrons and use them to convert carbon dioxide into methanol.

Using a special method based on in situ spectroscopy to visualize chemical reactions, the researchers were able to determine whether these molecules were reacting with methanol or Carbon monoxideThis is not the desired product: the researchers discovered that the path of the reaction is determined by the environment in which the carbon dioxide molecules react.

We tailor this environment by controlling how the CoPc catalyst is distributed. carbon nanotube “This surface treatment makes it eight times more likely that methanol can be produced from carbon dioxide,” said study co-author Robert Baker, professor of chemistry and biochemistry at Ohio State University. “This discovery could improve the efficiency of other catalytic processes and have far-reaching implications in other fields.”

“When you convert carbon dioxide into other substances, you can make a variety of different molecules,” he says, “and methanol is by far one of the most desirable because it has such a high energy density that it can be used directly as an alternative fuel.”

Converting waste molecules into useful products is not a new phenomenon, but until now researchers have not been able to observe how the reactions actually occur, which could provide key insights for optimizing and improving the process.

“You might be able to empirically optimize how something works, but you don’t actually understand why it works or why one catalyst is better than another,” said Baker, who specializes in surface chemistry, a field that studies how catalysts work. Chemical reaction It changes when it appears on the surface of different objects. “These are very difficult questions to answer.”

But with the help of special techniques and computer modeling, the team came much closer to understanding the complex process. In this study, the researchers used a new type of vibrational spectroscopy that allowed them to observe the behavior of molecules at the surface, said Quanson Chu, lead author of the study and a former Presidential Research Fellow at Ohio State University, whose challenging measurements were essential to the discovery.

“The vibrational signatures told us it was the same molecule that existed in two different reactive environments,” Chu said, “and we were able to correlate that one of these reactive environments was responsible for producing methanol, a valuable liquid fuel.”

Closer analysis also revealed that these molecules directly interact with supercharged particles called cations, which power the process of methanol production, according to the study.

More research is needed to learn what else these cations enable, but discoveries like this could be key to realizing more efficient ways to produce methanol, Baker said.

“We’re looking at a very important system and learning things we’ve long wondered about,” Baker said. “Understanding the unique chemical reactions that occur at the molecular level is critical to making these applications possible.”

Methanol produced from renewable electricity is not only a low-cost fuel for planes, cars, ships and other vehicles, but it could also be used for heating, power generation and to power future chemical discoveries.

“There are a lot of exciting things that can happen based on what we learn here, some of which we’ve already started working on together,” Baker said. “Work is underway.”