Czech researchers develop advanced photocathode to convert CO2 into ethanol
In the Czech Republic, researchers at Charles University in Prague have developed an advanced photocathode that helps convert the greenhouse gas carbon dioxide into pure ethanol using sunlight. The new technology solves a long-standing problem of material degradation in water, achieves record conversion efficiency and opens the way toward sustainable production of green fuels. The paper is published in the journal Advanced Energy Materials.
Converting carbon dioxide (CO2) into useful fuels using solar energy represents the holy grail of modern green chemistry. The device enabling this conversion is called a solar reactor. Its key element is a photocathode: a material that absorbs light and enables the chemical reaction. Cuprous oxide has long appeared to be an ideal material because it is inexpensive, readily available and excels at capturing sunlight. In practice, however, it faced a fundamental obstacle: In an aqueous environment under light, it transforms and degrades extremely rapidly—much like iron undergoing swift corrosion—and loses its functionality within tens of minutes.
The team resolved this issue by creating a unique “nano-sandwich.” The scientists combined cuprous oxide with advanced two-dimensional materials called MXenes and, through precisely controlled heating, created an ultrathin layer of titanium dioxide on their surface. MXenes modified in this way can rapidly drain electric charge from the cuprous oxide, thereby slowing its decomposition. At the same time, they use the charge to convert carbon dioxide into liquid fuel.
Category: Research
