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Chem. Mater. 2002, 14, 1576-1584
Inorganic Clusters as Single-Source Precursors for Preparation of CdSe, ZnSe, and CdSe/ZnS Nanomaterials Scott L. Cumberland, Khalid M. Hanif, Artjay Javier, Gregory A. Khitrov, Geoffrey F. Strouse,* Stephen M. Woessner, and C. Steven Yun Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106 Received July 31, 2001. Revised Manuscript Received February 25, 2002
Molecular inorganic clusters, which are stable under ambient conditions, can be used as convenient single-source precursors for controlled preparation of 2-9-nm CdSe and CdSe/ ZnS nanocrystals and 2-5-nm nanocrystals of ZnSe. The use of a cluster-based single-source precursor allows nanomaterial growth to be initiated at low temperature without the pyrolytic step for nucleus formation traditionally required for lyothermal growth processes. The elimination of the pyrolytic step allows greater synthetic control, slow thermodynamic growth at lower temperatures, high crystallinity, and reaction scalability (>50 g/L) while maintaining size dispersity at ∼5%.
Introduction The observation of quantum-confinement effects in semiconductor nanomaterials has generated substantial interest for applications for device technologies utilizing the novel optical and transport properties in these structures.1,2 The trend in nanomaterial synthesis has been the development of smaller, highly uniform, lowerdimensionality materials (quantum dots) where the quantum-confinement effects are large. In fact, the great strides in understanding the physical properties of these materials can be linked to developments in solvothermal preparative routes that allow monodisperse (metal and semiconductor) quantum dots to be readily prepared with high optical quality and a high degree of crystallinity.3 As interest in these materials shifts from fundamental studies to the use of these materials in device applications, the focus has shifted to the development of a reliable and reproducible method for largescale synthesis (greater than 1 g) of organically passi* Corresponding author: Prof. G. F. Strouse. Fax: 805.893.5326. E-mail:
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vated materials exhibiting mono-dispersity in shape and size (
