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Recently, N‐heterocyclic carbenes (NHCs) are explored as anchor groups to bind organic ligands to colloidal gold (i.e. gold nanoparticles, Au NPs), yet these efforts are confined to non‐conjugated ligands so far—that is, focused solely on exploiting the stability aspect. Using NHCs to link Au NPs and electronically active organic components, for example, conjugated polymers (CPs), will allow capitalizing on both the stability as well as the inherent conductivity of the NHC anchors. Here, we report three types of Br‐NHC‐Au‐X (X=Cl, Br) complexes, which, when used as starting points for Kumada polymerizations, yield regioregular poly(3‐hexylthiophenes)‐NHC‐Au (P3HTs‐NHC‐Au) with narrow molecular weight distributions. The corresponding NPs are obtained via direct reduction and show excellent thermal as well as redox stability. The NHC anchors enable electron delocalization over the gold/CP interface, resulting in an improved electrochromic response behavior in comparison with P3HT‐NHC‐Au. [ABSTRACT FROM AUTHOR]

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Dieser Aufsatz befasst sich mit dem Bereich der organisch‐anorganischen Nanokomposite, wobei der Schwerpunkt auf Materialien liegt, die einen signifikanten Grad elektronischer Kopplung über die Hybridgrenzfläche aufweisen. Diese Nanokomposite durchlaufen verschiedenste Ladungs‐ und Energietransferprozesse und ermöglichen optoelektronische Anwendungen in Bauelementen, welche auf der Nutzung von Singulettspaltung, der Gewinnung von Triplett‐Exzitonen, der Photonen‐Aufwärtskonvertierung oder dem Transfer heißer Ladungsträger beruhen. Wir diskutieren die physikalische Chemie der gängigsten organischen und anorganischen Komponenten. Ausgehend davon entwickeln wir Synthese‐ und Assemblierungsstrategien sowie Designkriterien auf Material‐ und Bauelementebene, mit Hinblick auf Photovoltaik, Spin‐Speicher und optischen Hochkonvertern. Die vorgestellten Ergebnisse legen nahe, dass die zukünftige Forschung auf diesem Gebiet auf ein besseres Verständnis des Bindungsmotivs und der molekularen Orientierung an der Hybridgrenzfläche ausgerichtet werden sollte. [ABSTRACT FROM AUTHOR]

Recently, N-heterocyclic carbenes (NHCs) are explored as anchor groups to bind organic ligands to colloidal gold (i.e. gold nanoparticles, Au NPs), yet these efforts are confined to non-conjugated ligands so far-that is, focused solely on exploiting the stability aspect. Using NHCs to link Au NPs and electronically active organic components, for example, conjugated polymers (CPs), will allow capitalizing on both the stability as well as the inherent conductivity of the NHC anchors. Here, we report three types of Br-NHC-Au-X (X=Cl, Br) complexes, which, when used as starting points for Kumada polymerizations, yield regioregular poly(3-hexylthiophenes)-NHC-Au (P3HTs-NHC-Au) with narrow molecular weight distributions. The corresponding NPs are obtained via direct reduction and show excellent thermal as well as redox stability. The NHC anchors enable electron delocalization over the gold/CP interface, resulting in an improved electrochromic response behavior in comparison with P3HT-NHC-Au., (© 2020 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

We review the field of organic-inorganic nanocomposites with a focus on materials that exhibit a significant degree of electronic coupling across the hybrid interface. These nanocomposites undergo a variety of charge and energy transfer processes, enabling optoelectronic applications in devices which exploit singlet fission, triplet energy harvesting, photon upconversion or hot charge carrier transfer. We discuss the physical chemistry of the most common organic and inorganic components. Based on those we derive synthesis and assembly strategies and design criteria on material and device level with a focus on photovoltaics, spin memories or optical upconverters. We conclude that future research in the field should be directed towards an improved understanding of the binding motif and molecular orientation at the hybrid interface., (© 2020 The Authors. Published by Wiley-VCH GmbH.)

To date, it has not been possible to combine the high optical quality of silver particles with the good chemical stability and synthetic convenience in a fully aqueous system, while simultaneously allowing chemical surface functionalization. We present a synthetic pathway for future developments in information, energy and medical technology where strong optical/electronic properties are crucial. Therefore, the advantages inherent to gold are fused with the plasmonic properties of silver in a fully aqueous Au/Ag/Au core-shell shell system. These nanoparticles inherit low dispersity from their masked gold cores, yet simultaneously exhibit the strong plasmonic properties of silver. Protecting the silver surface with a thin gold layer enables oxidant stability and functionality without altering the Ag-controlled optical properties. This combines both worlds-optical quality and chemical stability-and is not limited to a specific particle shape., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We present a bottom-up assembly route for a large-scale organization of plasmonic nanoparticles (NPs) into three-dimensional (3D) modular assemblies with core/satellite structure. The protein-assisted assembly of small spherical gold or silver NPs with a hydrophilic protein shell (as satellites) onto larger metal NPs (as cores) offers high modularity in sizes and composition at high satellite coverage (close to the jamming limit). The resulting dispersions of metal/metal nanoclusters exhibit high colloidal stability and therefore allow for high concentrations and a precise characterization of the nanocluster architecture in dispersion by small-angle X-ray scattering (SAXS). Strong near-field coupling between the building blocks results in distinct regimes of dominant satellite-to-satellite and core-to-satellite coupling. High robustness against satellite disorder was proved by UV/vis diffuse reflectance (integrating sphere) measurements. Generalized multiparticle Mie theory (GMMT) simulations were employed to describe the electromagnetic coupling within the nanoclusters. The close correlation of structure and optical property allows for the rational design of core/satellite nanoclusters with tailored plasmonics and well-defined near-field enhancement, with perspectives for applications such as surface-enhanced spectroscopies.