Microwave Synthesis of CdSe and CdTe Nanocrystals in Nonabsorbing Alkanes Aaron L. Washington II and Geoffrey F. Strouse* Department of Chemistry and Biochemistry, Florida State UniVersity, Tallahassee, Florida 32306-4390 Received December 26, 2007; E-mail: Strouse@chem.fsu.edu Abstract: Controlling nanomaterial growth via the “speciﬁc microwave effect” can be achieved by selective heating of the chalcogenide precursor. The high polarizability of the precursor allows instantaneous activation and subsequent nucleation leading to the synthesis of CdSe and CdTe in nonmicrowave absorbing alkane solvents. Regardless of the desired size, narrow dispersity nanocrystals can be isolated in less than 3 min with high quantum efﬁciencies and elliptical morphologies. The reaction does not require a high temperature injection step, and the alkane solvent can be easily removed. In addition, batch-to-batch variance in size is 4.2 ( 0.14 nm for 10 repeat experimental runs. The use of a stopped-ﬂow reactor allows near continuous automation of the process leading to potential industrial beneﬁts. 1. Introduction Over the past decade, there has been a vast amount of work to optimize the synthetic methodology for the II-VI (CdS, 1 CdSe, 2 CdTe 3 ) nanocrystalline semiconductors, leading to commercially available materials and applications for a wide range of technologies. 4–6 The synthetic methods for preparation of nanocrystals have improved by optimizing the reagents, ligands, solvents, and the general approach. 2b,7–9 The initial synthetic breakthrough in the control of size dispersity by Murray 10 led to the recent results demonstrating the use of nonorganometallic precursors for prepara- tion of CdSe based on CdO or Cd stearate by the research group of Peng. 11 Breakthroughs by Alivisatos, 12 Hyeon, 13 El-Sayed, 14 and Peng 15 have shown remarkable control over the shape and morphology of the nanocrystals. 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