Researchers have developed a molecule that uses light or electricity to efficiently convert the greenhouse gas carbon dioxide into a carbon-neutral fuel source.
The molecule employs a nanographene complex to absorb light and drive the conversion of carbon dioxide to carbon monoxide, researchers said.
It is a “new milestone in the quest to recycle carbon dioxide in the Earth’s atmosphere into carbon-neutral fuels and other materials,” said Liang-shi Li, associate professor at Indiana University in the United States.
Burning fuel, such as carbon monoxide, produces carbon dioxide and releases energy.
Turning carbon dioxide back into fuel requires at least the same amount of energy.
A major goal among scientists has been decreasing the excess energy needed.
This is exactly what Li’s molecule achieves: requiring the least amount of energy reported thus far to drive the formation of carbon monoxide.
The molecule is a nanographene-rhenium complex connected via an organic compound known as bipyridine.
It triggers a highly efficient reaction that converts carbon dioxide to carbon monoxide.
The ability to efficiently and exclusively create carbon monoxide is significant due to the molecule’s versatility.
“Carbon monoxide is an important raw material in a lot of industrial processes,” Li said.
“It’s also a way to store energy as a carbon-neutral fuel since you’re not putting any more carbon back into the atmosphere than you already removed. You’re simply re-releasing the solar power you used to make it,” he said.
The secret to the molecule’s efficiency is nanographene because the material’s dark color absorbs a large amount of sunlight.
The new molecule takes advantage of the light-absorbing power of nanographene to create a reaction that uses sunlight in the wavelength up to 600 nanometres – a large portion of the visible light spectrum.
The research was published in the Journal of the American Chemical Society.