FEB. 12 Fayetteville, Arkansas–A University of Arkansas research team has developed a safe alternative to semiconductor nanocrystals made of toxic materials that explode when mishandled. These nanocrytals can be used in semiconductor, energy storage, optoelectronics, and medical industries.
For the past 10 years, scientists have formed cadmium chalcogenide nanocrystals using the hazardous material dimethylcadmium, a toxic reagent that is costly, unstable at room temperature, and explosive at higher temperatures.
“We can use common, safe reagents to makes these nanocrystals,” says Xiaogang Peng, assistant professor of chemistry and biochemistry.
Peng and colleagues replaced the dimethylcadmium with a less expensive and more stable reagent, cadmium oxide. This reagent is less toxic and is easy to acquire and store. The researchers discovered that starting with cadmium oxide, they could make uniformly-sized nanocrystals using several different substrates–another advantage over the dimethylcadmium method, which produced uniform crystals of only one kind.
Using the new method, Peng’s group has synthesized nanocrystals in size ranges 4 times greater than before, and is using different solvent systems and precursors to create nanocrystals with different properties.
“This new method is very affordable,” Peng says. “Many groups will now jump into this field, and many applications will come out.”