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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... 

Abstract Nanohybrids based on van der Waals (vdW) heterostructures of two dimensional (2D) atomic materials have recently emerged as a unique scheme for designing high‐performance quantum sensors. This work explores vdW nanohybrids for photodetection, which consist of graphene decorated with intermingled transition‐metal dichalcogenide (TMDC) nanodiscs (TMDC‐NDs) obtained using wafer‐size, layer‐by‐layer growth. The obtained TMDC‐NDs/graphene nanohybrids take advantage of strong quantum confinement in graphene for high charge mobility and hence high photoconductive gain, and localized surface plasmonic resonance (LSPR) enabled on the TMDC‐NDs for enhanced light absorption. Since the LSPR depends on the nanostructure's size and density, intermingled TMDC‐NDs of different kinds of TMDCs, such as WS₂(W) and MoS₂(M), have been found to allow small‐size, high‐concentration TMDC‐NDs to be achieved for high photoresponse. Remarkably, high photoresponsivity up to 31 A/W (550 nm wavelength and 20 µW cm⁻²light intensity) has been obtained on the WMW‐NDs/graphene nanohybrids photodetectors made using three consecutive coatings of WS₂(1st and 3rd coating) and MoS₂(2nd coating), which is considerably higher by a factor of ≈4 than that of the counterparts MoS₂‐ND/graphene or WS₂‐NDs/graphene devices. This result provides a facile approach to control the size and concentration of the TMDC‐NDs for high‐performance, low‐cost optoelectronic device 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. 

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. 

ABSTRACT Colloidal quantum dot/graphene (QD/Gr) nanohybrids rely on strong quantum confinement and offer a promising platform to design high‐performance quantum sensors such as photodetectors. In QD/Gr nanohybrid photodetectors, QDs absorb the incident light, and the spectral range is determined by the QD's semiconductor bandgap with moderate tunability by QD size, which presents a challenge for QDs/Gr nanohybrids to be used for detection of photons beyond such a conventional bandgap‐determined spectral range. In this work, we explored coupled self‐scintillation and X‐ray photodetection in PbS QD/Gr nanohybrids of sub‐micron active layer thickness for compromised X‐ray self‐scintillation by Pb of high X‐ray cross section and high‐gain detection enabled by graphene on both rigid and flexible substrates. An additional critical step found to suppress noise induced by interaction of polar molecules with dangling bonds on the QD surface was achieved by a poly(methyl methacrylate) capping layer, resulting in significantly improved signal‐to‐noise ratio. This allows a maximum X‐ray sensitivity of 280 C Gy⁻¹cm⁻², together with high responsivity in visible to infrared range on the order of 10 A/W. This result has demonstrated that the conventional bandgap‐determined spectral range can be significantly expanded through design of the QD/Gr nanohybrids. The demonstrated performance and mechanical flexibility provide a pathway toward durable, flexible quantum dot‐based detectors for multi‐spectrum sensing.