Publications by authors named "Oleg Semyonov"

Porphyrinic metal-organic frameworks (MOFs) offer high surface areas and tunable catalytic and optoelectronic properties, making them versatile candidates for applications in phototherapy, drug delivery, photocatalysis, electronics, and energy storage. However, a key challenge for industrial integration is the rapid, cost-effective production of suitable sizes. This study introduces Zr(IV) alkoxides as metal precursors, achieving ultrafast (∼minutes) and high-yield (>90%) synthesis of three well-known Zr-based porphyrinic MOF nanocrystals: MOF-525, PCN-224, and PCN-222, each with distinct topologies.

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Diversification of polymer waste recycling is one of the solutions to improve the current environmental scenario. Upcycling is a promising strategy for converting polymer waste into molecular intermediates and high-value products. Although the catalytic transformations into small molecules have been actively discussed, the methods and characteristics of upcycling into new materials have not yet been addressed.

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Structural electronics, as well as flexible and wearable devices are applications that are possible by merging polymers with metal nanoparticles. However, using conventional technologies, it is challenging to fabricate plasmonic structures that remain flexible. We developed three-dimensional (3D) plasmonic nanostructures/polymer sensors via single-step laser processing and further functionalization with 4-nitrobenzenethiol (4-NBT) as a molecular probe.

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Porous architectures characterized by parallel channels arranged in honeycomb or rectangular patterns are identified in two polymorphic crystals of a zwitterionic 4-(aryliodonio)-benzenesulfonate. The channels are filled with disordered water molecules which can be reversibly removed on heating. Consistent with the remarkable strength and directionality of the halogen bonds (XBs) driving the crystal packing formation, the porous structure is stable and fully preserved on almost quantitative removal and readsorption of water.

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Here, we present a new family of hierarchical porous hybrid materials as an innovative tool for ultrasensitive and selective sensing of enantiomeric drugs in complex biosamples via chiral surface-enhanced Raman spectroscopy (SERS). Hierarchical porous hybrid films were prepared by the combination of mesoporous plasmonic Au films and microporous homochiral metal-organic frameworks (HMOFs). The proposed hierarchical porous substrates enable extremely low limit of detection values (10 M) for pseudoephedrine in undiluted blood plasma due to dual enhancement mechanisms (physical enhancement by the mesoporous Au nanostructures and chemical enhancement by HMOF), chemical recognition by HMOF, and a discriminant function for bio-samples containing large biomolecules, such as blood components.

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Broadband reduction of light reflection from the surface of InP wafers after high-temperature annealing in air has been observed. In the transparency region of the material, the reflection drop is accompanied by increasing transmission of light through the wafer. The spectral position of a deep minimum of the reflection coefficient can be tuned, by varying the temperature and the time of annealing, in a wide spectral range from ultraviolet to infrared.

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We describe the design, properties, and performance of an excitation-emission (EE) fluorimeter that enables spectral characterization of an object simultaneously with respect to both its excitation and its emission properties. Such devices require two wavelength-selecting elements, one in the optical path of the excitation broadband light to obtain tunable excitation and the other to analyze the resulting fluorescence. Existing EE instruments are usually implemented with two monochromators.

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