Electrochemistry—the study of how electricity drives chemical reactions—is at the heart of a promising new approach to tackling climate change and meeting global energy demands. The Wang Research Lab at Yale is currently exploring ways to convert carbon dioxide (CO2), a greenhouse gas and pollutant, into valuable products like methanol, which can be employed as a high-energy fuel.
To do this efficiently, scientists use catalysts, which are molecules that activate specific chemical reactions. Ideally, catalysts are both selective, producing only the desired product, and efficient, minimizing energy input while maximizing useful output.
About six years ago, the team discovered a catalyst that could help convert CO2 into methanol. However, the process faced a hurdle: CO2 had to first be converted into carbon monoxide (CO) before it could become methanol, and this step was slowing everything down. Their innovation was to introduce a second catalyst with a different active site—essentially a second reaction location—designed to speed up that initial conversion.
“The original catalyst only has one kind of active site,” said Jing Li, a postdoctoral associate in Wang’s research group and the first author of the study. “So, we introduced a second molecule [with] a second active site, to help with the bottleneck—the inefficient conversion of CO2 to CO.”
The result was a more stable and efficient system that increased methanol production with lower energy input. While the findings are promising, the team acknowledges that practical, large-scale applications are still further on the horizon. “Even though we’ve reached very high efficiency for making methanol, we’re still a little far from practical industrial applications,” Li said. “The cost of electricity is still high, so we need to improve energy efficiency. “Looking ahead, the Wang Research Lab hopes to develop even better catalysts—ones that could one day make CO2 reduction a commercially viable pathway to fuels, amino acids, and even sugars.