Tuesday, June 18, 2024

Converting carbon dioxide into fuel using solar energy

The sunlight is the ultimate source of energy. The amount of power from the Sun that strikes the Earth’s surface in an hour is more than the entire world’s energy consumption in a year. Global energy-related carbon dioxide emission is also increasing.

Now, an international team of researchers led by Lund University in Sweden made a carbon capture technology breakthrough that uses solar power to convert carbon dioxide into fuel or another useful chemical. The team used a combination of advanced materials that absorb sunlight use its energy to convert carbon dioxide and ultra-fast laser spectroscopy used to map exactly what happens in that process.

For their experiment, the researchers turned to a porous organic material called COF – covalent organic framework, which is known for absorbing sunlight very efficiently. By adding a so-called catalytic complex to COF, they succeeded in converting carbon dioxide to carbon monoxide without any additional energy.

“The conversion to carbon monoxide requires two electrons. When we discovered that photons with blue light create long-lived electrons with high energy levels, we could simply charge COF with electrons and complete a reaction”, says Kaibo Zheng, a chemistry researcher at Lund University.

The researchers hope that in the future, the discovery can be used to develop larger units that can be used on a global level to, with the help of the Sun, absorb carbon dioxide from the atmosphere and convert it into fuel or chemicals. They say a lot of work is still needed, though the initial steps are encouraging.

“We have completed two initial steps with two electrons. Before we can start thinking about a carbon dioxide converter, many more steps need to be taken, and probably even our first two must be refined. But we have identified a very promising direction to take”, concludes Tönu Pullerits, a chemistry researcher at Lund University.

The breakthrough could be an important piece of the puzzle in reducing the levels of greenhouse gases in the atmosphere in the future.

There are several carbon capture facilities in work, including Climeworks’ Orca direct air capture and storage plant that permanently removes millions of tonnes of CO2 from the air. Researchers developed a new method to capture 99% of carbon dioxide from air using a novel electrochemical system powered by hydrogen. This could be one of the many solutions to overcome the climate crisis we are facing.