This Artificial Leaf Could Be the Future of Alternative Fuels

Climate change is an issue that continues to worsen each year, but researchers have developed a possible solution to this problem: an artificial, fuel-producing leaf. Carbon dioxide levels in the atmosphere are at a record high, with over two million pounds of carbon dioxide emitted into the air each second. In order to even have a chance at solving climate change, we must not only emit less carbon dioxide, but also remove what has already been released.

Driven by this mission, an international team of researchers from the University of Waterloo, Ontario, have created an artificial leaf that mimics the carbon-removing abilities of an actual plant (which are made possible by cellular respiration, the reverse process of photosynthesis). But instead of using carbon dioxide to create fuel for itself, the artificial leaf will produce a carbon-neutral fuel. “We’re using carbon dioxide and water and sunlight as an input, and producing methanol and oxygen as a product,” says Yimin Wu, an engineering professor at the University of Waterloo who led the research team.

The team’s process uses a red-hued powder called cuprous oxide, which is created when glucose, copper acetate, sodium hydroxide, and sodium dodecyl sulfate are added to water that has been heated to a certain temperature. The powder acts as a catalyst when it is mixed with water and carbon dioxide. A solar energy simulator then shines a beam of white light into the solution, which triggers a chemical reaction that produces oxygen and methanol. The solution is heated, and the methanol is captured as it evaporates.

Like Wu’s team, researchers at the University of Cambridge have created an artificial leaf that uses photosynthesis to create synthetic gas. “Syngas” is currently used in a wide range of cooking products, plastic materials, and fertilizers. Production of the gas involves using natural gas or coal, which releases harmful greenhouse gases into the atmosphere. However, the syngas-producing artificial leaf uses clean energy sources and does not release greenhouse gases into the air, making it a viable competitor with more traditional forms of energy.

The leaf mimics photosynthesis by combining sunlight, water, and carbon dioxide with a cobalt catalyst to start a chemical reaction. This reaction then produces carbon monoxide and hydrogen, creating syngas which can be converted into liquid fuel. But unlike the syngas-producing leaf, Wu’s artificial leaf skips the intermediate step entirely and creates clean fuel directly from the chemical reaction.

Wu’s research is groundbreaking for two reasons. First, removing carbon dioxide from the atmosphere can slow down climate change considerably if performed on a large scale. Second, alternative fuels will allow people to continue using their fuel-powered vehicles, which would give us more time to transition to a carbon-neutral lifestyle. According to Wu, “This technology is expected to reduce CO2 emission from oil companies, automobile companies, and steel companies. It can also provide clean and sustainable fuels, methanol, for vehicles and aircrafts. Methanol is also a feedstock in chemical industry [sic] to make plastics and fibers. This provides a solution to reduce CO2 emission and produce sustainable fuels for green economy.”

Though alternative fuels will not replace fossil fuels just yet, Wu is optimistic about his research. He plans to increase the methanol yield in order to improve the efficiency of the technology, and he hopes to commercialize the process. Wu plans to use carbon dioxide captured from the steel industry, automotive industry, or even the oil-drilling industry, which would help remove carbon dioxide from the atmosphere. “It helps fight climate change, reducing CO2 emissions, but also provides sustainable energy,” Wu says.