What if the carbon dioxide building up in our atmosphere could be put to good use as fuel? For years chemists have chased a catalyst that could aid the reaction converting carbon dioxide to methane, a building block for many fuels – and now Duke University scientists have found just such a catalyst in tiny rhodium nanoparticles..

Duke University researchers converted carbon dioxide into methane with the help of rhodium nanoparticles, which harness ultraviolet light’s energy to catalyze carbon dioxide’s conversion into methane. Rhodium is one of Earth’s rarest elements, but according to Duke University it plays a key role in our daily lives by speeding up reactions in industrial processes like making detergent or drugs. Rhodium also helps break down toxic pollutants in our cars’ catalytic converters.

The fact that the scientists employed light to power the reaction is important. When graduate student Xiao Zhang tried heating up the nanoparticles to 300 degrees Celsius, the reaction did produce methane but also produced an equal amount of poisonous carbon monoxide. But when he instead used a high-powered ultraviolet LED lamp, the reaction yielded almost entirely methane.

Jie Liu, chemistry professor and paper co-author, said in a statement, “The fact that you can use light to influence a specific reaction pathway is very exciting. This discovery will really advance the understanding of catalysis.”

The scientists now hope to find a way to employ natural sunlight in the reaction, which Duke University says would be “a potential boon to alternative energy."