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A new type of organic dyad that can induce low-energy photosensitization has been developed; electron donor and electron acceptor units are boron dipyrromethene (BODIPY) and ortho-carborane (o-Cb), respectively. The new dyads consist of a V-shaped BODIPY-(o-Cb)-BODIPY molecular array in which two BODIPY units are substituted onto two adjacent carbon atoms of the central o-Cb. In the presence of the o-Cb unit, as an electron acceptor, significant fluorescence quenching was observed which indicated that photoinduced electron transfer (PET) had occurred from the end-on BODIPY units to the central o-Cb with PET efficiencies of 63–71%. As a result, the corresponding cationic and anionic species that are responsible for the charge transfer state were detected by the serial spectroelectrochemical studies: cationic BODIPY radicals at 400 nm at the applied voltage of 1.44 V and broad absorption bands of anionic o-Cb radicals in the range of 250–490 nm at −1.84 V. Transient absorption studies further confirmed the BODIPY radical anion at 540 nm and the o-Cb radical anion at 350–475 nm with a structureless broad band. [ABSTRACT FROM AUTHOR]

The incorporation of Sc3+ can stabilize calcite-phase LuBO3:Ce3+ to grow large-sized single crystals but leads to the significant degradation of scintillation performance. In the present work, alkali metal ion (A+ = Li+, Na+, K+)-incorporated (Lu, A, Sc)BO3:Ce was rapidly synthesized in batches via a high-throughput sol–gel method. The aliovalent substitution of Lu3+ with A+ is balanced by the generation of oxygen vacancies by forming complexes. Thanks to the increased oxygen vacancies, the luminescence and XEL intensity of (Lu, Li, Sc)BO3:Ce are significantly enhanced by 2.2 times and 1.9 times, respectively. Further, the incorporation of A+ is attributed to the improved transition efficiency of charge carriers. The prepared scintillation screen fabricated with LASBO:Ce and PMMA shows that the spatial resolution can reach 8.6 lp mm−1, indicating its potential application in efficient and low-cost non-destructive X-ray detection. This work is of great significance in improving the luminescence and scintillation performance of (Lu, Sc)BO3:Ce single crystals and thin films and their application in the scintillation field. [ABSTRACT FROM AUTHOR]

Conversion of carbon dioxide (CO2) into useful chemicals is an important and urgent task from the energy and environment perspective. Herein, through a post-synthetic modification (PSM) approach, we synthesized three new metal–organic frameworks (MOFs) UiO-68-PSMs with different functional groups, namely, UiO-68-F, UiO-68-CH3 and UiO-68-OCH3, for the photocatalytic reduction of CO2. By introducing electron-withdrawing and electron-donating groups, UiO-68-PSMs showed different performance for the selective photocatalytic reduction of CO2 to CO because of change in charge separation and band gap of UiO caused by the presence of different functional groups. [ABSTRACT FROM AUTHOR]

Nano/microscale lanthanide porous coordination polymer MIL-103(Eu) [Eu(BTB)] (H3BTB = 4,4′,4′′-benzene-1,3,5-triyl-tribenzoic acid) crystals have been fabricated at room temperature by a facile, convenient and environmentally friendly method. The structures of the products were confirmed by powder X-ray diffraction, and the crystal morphologies, including microrods, nanorods and nanospheres, were characterized by scanning electron microscopy. It is found that the addition of sodium acetate and the concentration of the reactants have an important impact on the morphology and size of the MIL-103(Eu) crystals. Gas adsorption measurements reveal that the products show high specific surface areas among the rare earth based coordination polymers and the MIL-103(Eu) nanorods can selectively adsorb CO2 over N2 under ambient conditions. Furthermore, all the products exhibit red emission corresponding to the 5D0→7F2 transition of the Eu(iii) ion, and MIL-103(Eu) nanorods display sensitive and selective sensing for Cu(ii) ions and acetone molecules in solution. [ABSTRACT FROM AUTHOR]

A facile and universal method was developed to evaluate the relative water stability of porous MOFs and morphological evolution was achieved by controlling the volume ratio of DMF and H2O. The relative water stability of the studied MOFs is in the order HKUST-1 ＞ MOF-505 ∼ UMCM-150 ＞ NOTT-101 ＞ DUT-23(Cu) ＞ [Zn2(BPnDC)2(DABCO)] ∼ [Cu3(TPTrC)2(DABCO)] ＞ MOF-5. In addition, DUT-23(Cu) [Cu6(BTB)4(BPY)3] (H3BTB = 4,4′,4′′-benzene-1,3,5-triyl-tribenzoic acid, BPY = 4,4′-bipyridine) nanoparticles obtained with a volume ratio of DMF and H2O of 18 : 2 show excellent adsorption capacity for methylene blue (MB) (814 mg g−1) with high selectivity compared with methyl orange, rhodamine B, and acid chrome blue K dyes due to the size and the electrostatic repulsion effects in aqueous solution. [ABSTRACT FROM AUTHOR]