Cheaper Solvent for Growing Quantum Dots

Synthesizing quantum dots is an expensive undertaking because these fluorescent semiconductor nanoparticles typically are grown in a pricey, high-boiling solvent such as trioctylphosphine oxide ($158 per L) or octadecene ($23 per L). Searching for cheaper alternatives, scientists at Rice University have found that quantum dots of comparable quality can be synthesized in heat-transfer fluids, which commonly are used to move heat between processing units at chemical plants (Nanotechnology 2005, 16, 2000). A team led by Michael S. Wong found that two heat-transfer fluids--Dowtherm A ($3 per L) and Therminol 66 ($10 per L)--can be used as solvents for preparing uniformly sized cadmium selenide quantum dots or quantum rods. The team's preferred solvent is Dowtherm A, a mixture of diphenyl ether and biphenyl. But the team also concluded that, under the appropriate conditions, just about any heat-resistant solvent could be used to grow quantum dots. That's sure to be good news for both producers and users of quantum dots, which show promise for electronics, fluorescence imaging, and optical coding.