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Persistent luminescence (PersL) materials show long-lasting emission after irradiation with excitation light. Usually, to obtain PersL, excitation with ultraviolet (UV) or visible light is necessary, which limits the use of this phenomenon when the material is in a non-transparent medium for excitation light. A solution to this problem comes from upconverting nanoparticles (UCNPs), which convert near-infrared light, usually not absorbed by such media as polymers or biological tissues, to higher-energetic UV photons, recharging the PersL phosphors. In this article, we report composite materials consisting of PersL phosphor and UCNPs, i.e. SrAl2O4:Eu2+ or ZnGa2O4:Cr3+ and upconverting LiYbF4:Tm3+@LiYF4 core@shell nanoparticles. These materials show dual-emission properties - bright upconversion from near-infrared (NIR at 975 nm) to ultraviolet (UV at 347 nm) and long-lasting PersL in the visible light range. The obtained composite materials present intense, persistent luminescence after the NIR laser excitation. This article proves efficient energy transfer from UCNPs to PersL phosphor and opens new possibilities in the design and synthesis of composite materials. By employing the high-resolution 3D-printing technology, we experimentally confirmed the possibility of multi-modal optical information storage by applying the synthesized materials, developing multi-dimensional microstructured patterns with QR code, letters and first bi-modal, single- and double-layered 8-bit codes based on the combination of PersL and upconversion emission. [ABSTRACT FROM AUTHOR]

25 years after the first papers on the development of Periodic Mesoporous Organosilicas, and in this special issue in honor of prof. Ozin who stood at the cradle of PMOs, we here report for the first time an "acac-PMO" with the acac-functionality intact and embedded in the organic environment of the linker. Periodic mesoporous organosilicas (PMOs) have emerged as versatile sensors due to their stability, low toxicity, and scalability. This study reports for the first time on embedding the acetylacetone (acac) group into the PMO backbone. This integration of acac into the PMO framework opens new applications in both sensing and catalysis. The Eu3+ grafted acac-PMOs demonstrate enhanced sensitivity, with a detection limit of 108 nM, and high selectivity in aqueous copper (Cu2+) ion sensing. Additionally, these novel PMOs show high catalytic efficiency in Mannich reactions. [ABSTRACT FROM AUTHOR]

This study explores the potential of combining periodic mesoporous organosilicas (PMOs) with a fluorescent dye to develop a ratiometric thermometry system with enhanced stability, sensitivity, and biocompatibility. PMOs, ordered porous materials known for their stability and versatility, serve as an ideal platform. Curcumin, a natural polyphenol and fluorescent dye, is incorporated into PMOs to develop curcumin-functionalized PMOs (C-PMO) and curcumin-pyrazole-functionalized PMOs (CP-PMO) via hydrolysis and co-condensation. These PMOs exhibit temperature-dependent fluorescence properties. The next step involves encapsulating rhodamine B (RhB) dye within the PMO pores to create dual-emitting PMO@dye nanocomposites, followed by a lipid bilayer (LB) coating to enhance biocompatibility and dye retention. Remarkably, within the physiological temperature range, C-PMO@RhB@LB and CP-PMO@RhB@LB demonstrate noteworthy maximum relative sensitivity (Sr) values of up to 1.69 and 2.60% K−1, respectively. This approach offers versatile means to create various ratiometric thermometers by incorporating different fluorescent dyes, holding promise for future temperature sensing applications. [ABSTRACT FROM AUTHOR]

Porous organic polymers (POPs), and especially covalent triazine frameworks (CTFs), are being developed as the next generation of metal‐free heterogeneous photocatalysts. However, many of the current synthetic routes to obtain these photoactive POPs require expensive monomers and rely on precious metal catalysts, thus hindering their widespread implementation. In this work, a range of POPs was synthesized from simple unfunctionalized aromatic building blocks, through Lewis acid‐catalyzed polymerization. The obtained materials were applied, for the first time, as heterogeneous photocatalysts for the aromatization of N‐heterocycles. With the use of the most active material, denoted as CTF‐Pyr, which consists of photoactive pyrene and triazine moieties, a wide range of pyridines, dihydroquinoline‐5‐ones, tetrahydroacridine‐1,8‐diones and pyrazoles were obtained in excellent yields (70–99 %). Moreover, these reactions were carried out under very mild conditions using air and at room temperature, highlighting the potential of these materials as catalysts for green transformations. [ABSTRACT FROM AUTHOR]

Gallium (III) sulfide is a frontrunner for many energy storage and optoelectronic applications, which demand a deposition technique that offers a high level of control over thickness, composition, and conformality. Atomic layer deposition (ALD) is a potential technique in this regard. However, the state-of-the-art ALD processes for depositing Ga2S3 often lead to films that are amorphous and nonstoichiometric, and contain significant contaminations. Herein, we present a new plasma-enhanced atomic layer deposition (PE-ALD) process using the hexakis(dimethylamido)digallium precursor and H2S plasma coreactant to deposit high-quality Ga2S3 sulfide thin films and compare it to the thermal ALD process using the same reactants. While both cases exhibit typical ALD characteristics, substantial disparity is observed in the material properties. The PE-ALD process deposits crystalline Ga2S3 sulfide thin films at a temperature as low as 125 °C with a growth per cycle of 1.71 Å/cycle. Additionally, the PE-ALD process results in smooth and stoichiometric Ga2S3 films without any detectable carbon and oxygen contamination. Grazing incidence wide-angle x-ray scattering analysis indicates that the as-deposited Ga2S3 film crystallizes in a cubic structure with a preferred orientation along the [111] direction. The Ga2S3 film exhibits a transmittance of 70% and a bandgap of 3.2 eV with a direct transition. [ABSTRACT FROM AUTHOR]