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

Abstract

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.

O estado da arte da síntese de semicondutores nanocristalinos coloidais

“…Gaponik et al 29 descreveram o processo experimental para produção de nanocristais de ZnSe, a partir do borbulhamento do gás H 2 Se em uma solução precursora de zinco. Da mesma maneira, Rogach et al 30 conseguiram obter nanocristais de HgTe e Cd x Hg 1-x Te a partir da reação entre os íons Hg 2+ e o gás H 2 Te. As nanopartículas obtidas apresentaram uma ampla faixa de emissão espectral, de 700 a 1900 nm.…”

Liquid–Liquid Diffusion‐Assisted Crystallization: A Fast and Versatile Approach Toward High Quality Mixed Quantum Dot‐Salt Crystals

“…[11][12][13][14] Improving the characteristics and quality of QDs regarding synthetic Figure 1 a, a stable interface between the MeOH solution and the underlying NaCl-QD mixture instead of an instantaneous mixing is crucial for a successful crystallization. Through the subsequent diffusion of MeOH into water and the thereby reduced solubility, NaCl crystals with incorporated CdTe QDs are formed within hours.…”

Anomalous suppression of valley splittings in lead salt nanocrystals without inversion center

“…8 Although their crystalline structure has been experimentally established 9-11 the stoichiometry, point symmetry, and structural homogeneity of lead salt NCs grown by different procedures remain the subjects of discussions. [11][12][13] It is therefore important to study how the variations in NC structure affect the energies of confined electrons.…”