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The modular synthesis of a fluorene-based nanohoop containing six strained alkynes is described herein. We demonstrate its scalability using alkyne metathesis as the macrocyclization method and its reactivity with azides... 

Plasmonic metastructures have become valuable platforms for manipulating light based on polarization. While traditional approaches have focused on sorting light through front- or back-scattering, recent advances underscore the potential of in-plane light routing—guiding and separating photons across the surface of the metastructure itself. In this study, we investigate how lateral asymmetry in nanoantenna design—introduced along the direction of in-plane light propagation rather than the axis of illumination—can be leveraged for efficient polarization sorting. We focus on metasurfaces composed of arrays of both symmetric and asymmetric gold nanoantennas. Our results reveal that such structural asymmetry enables two distinct modes of operation: in one, photons with different polarizations are directed along separate in-plane paths; in the other, they follow the same axis but are emitted at different angles depending on their polarization. We further examine the spectral dependence of this sorting behavior and demonstrate that asymmetric metastructures can realize four-way polarization sorting, each with unique anisotropic characteristics. Our simulation results provide insight into how phase modulation of the scattered light—coupled into the substrate beneath the metasurface—is influenced by nanoantenna asymmetry. These findings pave the way for compact, on-chip implementations of the planar spin Hall effect and for simplified metasurfaces suited to sensing, optical switching, and beam steering applications. 

This review focuses on photocyclization reactions involving alkenes and arenes. Photochemistry opens up synthetic opportunities difficult for thermal methods, using light as a versatile tool to convert stable ground-state molecules into their reactive excited counterparts. This difference can be particularly striking for aromatic molecules, which, according to Baird’s rule, transform from highly stable entities into their antiaromatic “evil twins”. We highlight classical reactions, such as the photocyclization of stilbenes, to show how alkenes and aromatic rings can undergo intramolecular cyclizations to form complex structures. When possible, we explain how antiaromaticity develops in excited states and how this can expand synthetic possibilities. The review also examines how factors such as oxidants, substituents, and reaction conditions influence product selectivity, providing useful insights for improving reaction outcomes and demonstrating how photochemical methods can drive the development of new synthetic strategies. 

Geminal hyperconjugation is a key electronic effect that modulates bond distances, barrier widths, and thermochemical driving forces in heavy-atom tunneling reactions involving opening and closing three-membered rings. 

Nanohybrids of graphene and colloidal semiconductor quantum dots (QDs/Gr) provide a promising quantum sensing scheme for photodetection. Despite exciting progress made in QDs/Gr photodetectors in broadband from ultraviolet to short-wave infrared, the device performance is limited in middle-wave infrared (MWIR) detection. A fundamental question arises as to whether the thermal noiseinduced dark current and hence poor signal-to-noise ratio in conventional uncooled MWIR photodetectors persist in QDs/ Gr nanohybrids. Herein, we investigated noise, responsivity (R*), and specific detectivity (D*) in HgTe QDs/Gr nanohybrids, revealing that the noise and R* are decoupled in nanohybrids and each can be optimized independently toward its theoretical limit. Specifically, the noise in the QDs/Gr nanohybrids is dominated by that of graphene with a negligible effect from the dark current in HgTe QDs and can be optimized to its intrinsic limit by removing charge doping of adsorbed polar molecules on graphene. Furthermore, the R* is proportional to the photoconductive gain enabled by the strong quantum confinement in QDs and Gr. Achieving high gain in the MWIR spectrum, however, is challenging and requires elimination of charge traps primarily from the surface states of the narrow-bandgap semiconductor HgTe QDs. Using grain-rotation-induced grain-coalescence growth of single-layer and core/shell HgTe QDs, we show the that HgTe QDs surface states caused by Te deficiency can be dramatically suppressed, resulting in high gain up to 4.0 × 107 in the MWIR spectrum. The optimized noise and R* have led to high uncooled MWIR D* up to 2.4 × 1011 Jones, making nanohybrids promising to surpass the fundamental dark-current limit in conventional photodetectors. 

Aromaticity and antiaromaticity are pivotal concepts in chemistry, with significant implications for molecular properties and reactivity.