"We call it an artificial leaf because it mimics real leaves and the photosynthesis process," says Yimin A. Wu, professor of engineering at the Waterloo Institute of Nanotechnology.
Plants are among the most effective agents of carbon sequestration, a process by which carbon dioxide is blocked from the atmosphere. During photosynthesis, plants convert CO2 and water into oxygen and glucose thanks to the chlorophyll pigment in their leaves. They can do this with the help of sunlight, which absorbs chlorophyll to facilitate chemical reactions within plant cells.
In order to sequester more CO2, we can plant more plants. We can also increase the ability of plants to absorb CO2 from the air, for example by allowing them to grow larger roots or by adjusting their efficiency in capturing carbon.
A team of scientists from the University of Waterloo in Canada, California State University in the United States and the City University of Hong Kong have devised another way to capture CO2 from the atmosphere: creating an artificial leaf that mimics the functioning of real leaves.
Its artificial leaf converts CO2 into methanol, an alternative fuel that can then be used, they explain in a study published in the journal Nature Energy.
"We call it an artificial leaf because it mimics real leaves and the photosynthesis process," says Yimin A. Wu, a professor of engineering at the Waterloo Institute of Nanotechnology, who is the lead scientist behind the project, which he has been working on. For the past four years. “A leaf produces glucose and oxygen. We produce methanol and oxygen ”.
Their solution, if applied on a large enough scale, could help mitigate the effects of climate change and provide us with a useful substitute for fossil fuels at the same time.
"The key to the process is a cheap, optimized red powder called cuprous oxide," the researchers explain on the University of Waterloo website. “Designed to have as many eight-sided particles as possible, dust is created by a chemical reaction when four substances - glucose, copper acetate, sodium hydroxide, and sodium dodecyl sulfate - are added to water that has been heated to a particular temperature ”.
Mixed with water, the specially made power serves as a catalyst for a chemical reaction as carbon dioxide is pumped in and a solar simulator shines a beam of white light into the chemical solution to drive the reaction. The chemical reaction produces oxygen through a process that mimics photosynthesis.
At the same time, the CO2 in the powdered water solution is converted to methanol. The solution is heated so that the methanol can collect while evaporating. "This is the chemical reaction that we discovered," says Wu. "No one has done this before."
The scientist says the invention could soon be applied on a commercial scale and deployed to convert CO2e collected from major greenhouse gas emitters, such as power plants, vehicles and oil drills. "I am extremely excited about the potential of this discovery to change the game," says Wu.
"Climate change is an urgent problem and we can help reduce CO2 emissions and at the same time create an alternative fuel," he closed.