Quantum confined nanomaterials

Conjugated-Polymer/Quantum-Confined Nanomaterials-Based Hybrids for Optoelectronic Applications... 

Keywords Quantum confinement, quantum-confined nanomaterials (QCNs), quantum dots (QDs), tetrapods, nanocrystals, nanorods, carbon dots (C-dots), graphene quantum dots (GQDs), CdSe, CdS, CdTe, PbS, PbSe, blends, nanocomposites, in-situ polymerization, organic photovoltaics (OPVs), organic light-emitting diodes (OLEDs), dye-sensitized solar cells (DSSCs)... 

Synthetic Approaches for Quantum-Confined Nanomaterials (QCNs)... 

Like their inorganic counterparts, organic quantum confined nanomaterials (QCNs) also display size-dependent optoelectronic properties, though surface states, synthesis routes, and surface chemistry play much stronger... 

Conjugated-Polymer/Quantum-Confined Nanomaterials (CP/QCN) Hybrids... 

So far the principles and theoretical models that we discussed for the excited state dynamics including line shifts and broadening were developed originally for ions in bulk solids. Although the 4f electronic states are localized and exhibit little quantum confinement, the dynamics of electronic transitions may be subjected to quantum confinement arising from electron-phonon interactions. Modification of the existing theoretical models is required for their applications to lanthanides in nanomaterials. 

Nanoparticle materials are important because they exhibit unique properties due to size effects, quantum tunneling, and quantum confinement. As sizes of embedded particles are reduced to the nanometer scale, the surface-to-bulk ratio increases significantly. Therefore, surface effects can dominate bulk properties and an understanding of nanosurfaces becomes important. In this chapter, we discuss characterization of vacancy clusters that reside on surfaces of embedded nanoparticles as well as studies on the correlation of surface vacancy clusters to the properties of the nanomaterials. 

Optoelectronic nanodevices that rely on electric field effects in optical absorption and emission provide the ability to be controlled conveniendy using integrated electronic platforms. Semiconductor quantum dots are theoretically expected as an excellent candidate for such optoelectronic nanomaterials to show optical properties strongly dependent on electric field [1]. In the general class of quantum dots, chemically synthesized semiconductor nanocrystals also exhibit electric field effects, for example, as demonstrated in their optical absorption (e.g. the quantum confined Stark effect [2,3]) and in their optical emission as the Stark shift and luminescence quenching [4,5]). 

Optical and photonic properties. The efficiency of charge transfer over nanoscale distances and the quantum confinement of electrical carriers within nanoparticles are two factors that make nanomaterials optically different from bulk crystals. Nanophotonic properties can be linear and nonlinear, and can be finely tailored by controlling material dimensions and surface chemistry. Distinct color indicators may be based on surface plasmons the light output is dictated by the dielectric function of a nanomaterial and the shape of a nanoparticle. Specific needs include reactivity of nanoscale materials to electromagnetic radiation, including photoreactivity. 

Semiconductor nanoparticles offer distinct advantages over other materials owing to their specific quantum confinement effects, which allow fine-tuning the properties of their excited states by tailoring their size and shape. ° The main type of novel and emerging nanomaterials are discussed in the next sections along with the most intriguing results already disclosed. 

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