Infrared-Emitting Colloidal Nanocrystals: Synthesis, Assembly, Spectroscopy, and Applications

Photonics and Optoelectronics Group, Physics Department and Centre for NanoScience (CeNS), Ludwig-Maximilians-Universität München, Munich, Germany.
Small (Impact Factor: 8.37). 05/2007; 3(4):536-57. DOI: 10.1002/smll.200600625
Source: PubMed


Semiconductor nanocrystals produced by means of colloidal chemistry in a solvent medium are an attractive class of nanometer-sized building blocks from which to create complex materials with unique properties for a variety of applications. Their optical and electronic properties can be tailored easily, both by their chemical composition and particle size. While colloidal nanocrystals emitting in the infrared region have seen a burst of attention during the last decade there is clearly a paucity of review articles covering their synthesis, assembly, spectroscopic characterization, and applications. This Review comprehensively addresses these topics for II-VI, III-V, and IV-VI nanocrystals, examples being HgTe and Cd(x)Hg(1-) (x)Te, InP and InAs, and PbS, PbSe, and PbTe, respectively. Among the applications discussed here are optical amplifier media for telecommunications systems, electroluminescence devices, and noninvasive optical imaging in biology.

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