Synthesis of ZnO Nanoparticles/Nanofibers and Their Luminescence via Electrospinning

This article reports on the synthesis procedure of ZnO nanoparticles/nanofibers structure by electrospinning method using Zinc acetate and polyvinylpyrrolidone (PVP) surfactant as reagents and evaluates their luminescent properties. The microstructure of ZnO nanoparticles/nanofibers was observed by FE-SEM. The phase formation of ZnO nanoparticles/nanofibers was studied by XRD. ZnO nanoparticles/nanofibers structure shows strong luminescence centering at 660 nm, which has potential applications in solid-state lighting.

Intermolecular Charge-Transfer-Induced Strong Optical Emission from Herringbone H-Aggregates

Superior organic light-emitting transistors (OLETs) materials require two conventionally exclusive properties: strong luminescence and high charge mobilities. We propose a three-state model through localized diabatization to quantitative analyze excited state structures for various herringbone (HB) H-aggregates and demonstrate that for some investigated systems, the low-lying intermolecular charge-transfer (CT) state couples with the bright Frenkel exciton (FE) and forms a dipole-allowed S₁ that lies below the dark state, proceeding strong luminescence. Specifically, such conversion in luminescence properties occurs when the electron- and hole-transfer integrals ( and ) are of the same sign and is notably larger than the excitonic coupling (<i>J</i>), i.e., . This theoretical finding can not only explain and rationalize recent experimental results on DPA and dNaAnt, both with OLET property, but also unravel an exciting scenario where strong luminescence and high charge mobilities are compatible, which will considerably broaden the aperture of novel OLET design.

Intermolecular Charge-Transfer-Induced Strong Optical Emission from Herringbone H-Aggregates

Superior organic light-emitting transistors (OLETs) materials require two conventionally exclusive properties: strong luminescence and high charge mobilities. We propose a three-state model through localized diabatization to quantitative analyze excited state structures for various herringbone (HB) H-aggregates and demonstrate that for some investigated systems, the low-lying intermolecular charge-transfer (CT) state couples with the bright Frenkel exciton (FE) and forms a dipole-allowed S₁ that lies below the dark state, proceeding strong luminescence. Specifically, such conversion in luminescence properties occurs when the electron- and hole-transfer integrals ( and ) are of the same sign and is notably larger than the excitonic coupling (<i>J</i>), i.e., . This theoretical finding can not only explain and rationalize recent experimental results on DPA and dNaAnt, both with OLET property, but also unravel an exciting scenario where strong luminescence and high charge mobilities are compatible, which will considerably broaden the aperture of novel OLET design.

Fluorescent Detection of Carbon Disulfide by a Highly Emissive and Robust Isoreticular Series of Zr-Based Luminescent Metal Organic Frameworks (LMOFs)

Carbon disulfide (CS2) is a highly volatile neurotoxic species. It is known to cause atherosclerosis and coronary artery disease and contributes significantly to sulfur-based pollutants. Therefore, effective detection and capture of carbon disulfide represents an important aspect of research efforts for the protection of human and environmental health. In this study, we report the synthesis and characterization of two strongly luminescent and robust isoreticular metal organic frameworks (MOFs) Zr6(µ3-O)4(OH)8(tcbpe)2(H2O)4 (here termed 1) and Zr6(µ3-O)4(OH)8(tcbpe-f)2(H2O)4 (here termed 2) and their use as fluorescent sensors for the detection of carbon disulfide. Both MOFs demonstrate a calorimetric bathochromic shift in the optical bandgap and strong luminescence quenching upon exposure to carbon disulfide. The interactions between carbon disulfide and the frameworks are analyzed by in-situ infrared spectroscopy and computational modelling by density functional theory. These results reveal that both the Zr metal node and organic ligand act as the preferential binding sites and interact strongly with carbon disulfide.

Creation of Silicon-Vacancy Color Centers in Diamond by Ion Implantation

Silicon-vacancy (SiV) centers in diamond are gaining an increased interest for application, such as in quantum technologies and sensing. Due to the strong luminescence concentrated in its sharp zero-phonon line at room temperature, SiV centers are being investigated as single-photon sources for quantum communication, and also as temperature probes for sensing. Here, we discussed strategies for the fabrication of SiV centers in diamond based on Si-ion implantation followed by thermal activation. SiV color centers in high-quality single crystals have the best optical properties, but polycrystalline micro and nanostructures are interesting for applications in nano-optics. Moreover, we discuss the photoluminescence properties of SiV centers in phosphorous-doped diamond, which are relevant for the creation of electroluminescent devices, and nanophotonics strategies to improve the emission characteristics of the SiV centers. Finally, the optical properties of such centers at room and high temperatures show the robustness of the center and give perspectives for temperature-sensing applications.

Cr3+-activated Na3X2Li3F12 (X=Al, Ga, In) garnet phosphors with broadband NIR emission and high luminescence efficiency for potential biomedical application

With the repaid development of NIR pc-LED, it is urgent to develop novel NIR phosphor with broadband emission, strong luminescence and high thermal stability. Here, three isotypic garnet fluorides Na3X2Li3F12...