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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]

Ingenious dielectric tuning strategies are challenging to set up with high-efficiency microwave absorbing (MA) materials that absorb strongly at the ultrathin absorber level. In this work, an aerogel with a dual three-dimensional (3D) conductive network was constructed using a solvothermal and ice template-assisted freeze-drying process, namely, 1T-tungsten disulfide/carbon nanotubes-reduced graphene oxide (1T-WS2/CNT-rGO). Numerous small-scale staggered 2D nanosheets were assembled into nanoflower-like WS2, forming a unique conductive network. Meanwhile, the CNT-rGO acted as the 3D aerogel scaffold to support the WS2 and provided a 3D conductive network to facilitate electronic hopping. The tremendous 1T-phase thus introduced significantly promoted the charge transfer capability at the 1T/2H heterointerface and enriched the phase interface polarization. Benefiting from the synergistic effect of enhanced polarization loss and optimized impedance matching, the thickness of 1T-WS2/CNT-rGO was merely 1.15 mm corresponding to the minimum reflection loss (RLmin) of −56.63 dB; the maximum effective absorption bandwidth (EABmax) reached 3.84 GHz. Furthermore, the simulation results verified that the absorber coating could effectively suppress the radar cross-section (RCS) of strong metal scattering sources to different degrees. Consequently, the potential of 1T-WS2/CNT-rGO to be employed as the new generation of ultrathin and high-efficiency absorbers can be predicted. [ABSTRACT FROM AUTHOR]

Developing a low-frequency tunable microwave absorber for the normal use of sophisticated electric devices is an urgent requirement for dealing with electromagnetic pollution. Herein, we report the designed synthesis of a three-dimensional (3D) heterostructure constructed from multidimensional components, namely, MXene/CoNi/N-CNTs (nitrogen-doped carbon nanotubes). A uniform metal–organic-framework (MOF) ZIF-67/Co–Ni layered double hydroxide (LDH) core-shelled structure was first synthesized and then transformed into CoNi/N-CNTs via pyrolysis under a N2 atmosphere. Then, CoNi/N-CNTs were deposited on the surface of 2D MXene by electrostatic assembly to acquire a 3D superstructure nanocomposite. The advantages of low-dimensional components are fully utilized in the unique 3D heterostructure. The 3D conductive network is formed from 1D N-CNTs, and the synergistic effect of multiple loss mechanisms significantly facilitates its microwave absorption (MA) properties. Specifically, the material shows an optimal reflection loss (RL) of −52.64 dB at 3.12 GHz at a thickness of 3.8 mm, and an effective absorption bandwidth (EAB) from 2.8 to 3.52 GHz, which covers the S-band. Importantly, adjustable and efficient MA between the S and C band can be realized by modulating the loads of the CoNi/N-CNTs. Accordingly, the feasibility of designing a hierarchical 3D superstructure from low-dimensional components to deal with electromagnetic pollution can be audaciously predicted. [ABSTRACT FROM AUTHOR]

Thrombus, bacterial infections, and severe inflammation are still serious problems that have to be faced with blood-contacting materials. However, it is a great challenge to simultaneously meet the above functional requirements in a simple, economical and efficient method. As such, we put forward a robust and versatile coating strategy by covalently modifying the multi-pharmacological drug honokiol (HK) with an amine-rich polydopamine/polyethyleneimine coating, through which anticoagulant, antibacterial and anti-inflammatory properties were obtained (DPHc) simultaneously. The amine content in the DPHc coating was lower than the detection limit, while it contained abundant phenolic hydroxyl groups (49 μmol cm−2). Meanwhile, the 30 day drug release test confirmed that the drug was firmly modified on the surface of the coating without release. A systematic in vitro and ex vivo evaluation confirmed that the coating had significant anti-thrombotic properties. The antibacterial rates of the DPHc coating against Staphylococcus aureus and Escherichia coli reached 99.98% and 99.99%, respectively. In addition, subcutaneous implantation indicated that the DPHc coating also has excellent histocompatibility. To the best of our knowledge, this is the first study using HK as a coating material that can not only combat thrombosis and infection but also significantly inhibit inflammation associated with the use of blood-contacting materials, thus expanding the application of HK in the field of biomaterials. [ABSTRACT FROM AUTHOR]

Stabilizing metal nanoparticles (MNPs) with metal–organic frameworks (MOFs) has become a favorable pathway for developing efficient hybrid photocatalysts, while effective charge transfer within hybrid catalysts is largely elusive. In this work, we employed a semiconductor-like Zr-MOF, NH2-UiO-68, with an amino-functionalized linker and permanent porosity enabling the confinement of guest species for the first time. Pt NPs have been embedded inside (referred to as Pt@MOF), outside (referred to as Pt/MOF) or both inside and outside (referred to as Pt-MOF) of the flowerlike NH2-UiO-68 by varying synthetic methods and Pt NP amounts. Among these different hybrids, the 2 wt% Pt@NH2-UiO-68 sample presents the highest photocatalytic CO2 reduction activity under visible light irradiation, and is far superior to the 2 wt% Pt/NH2-UiO-68, 1 wt% Pt@NH2-UiO-68, and 4 wt% Pt-NH2-UiO-68 samples. The appropriate location and content of Pt NPs in the catalysts would facilitate the contact between Pt NPs and NH2-UiO-68, which is beneficial to form Pt-MOF heterojunctions, thereby achieving efficient charge transfer in the photocatalytic process. More importantly, effective charge transfer from NH2-UiO-68 to the excited Pt NPs via Pt-MOF Schottky junctions can accordingly inhibit the recombination of photogenerated charge carriers, ultimately leading to the enhancement of photocatalytic activity. [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]

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]

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]

Electron donor–acceptor (D–A) systems with a triphenylamino moiety (D) and ortho-carborane (A) show three kinds of intriguing emissions that can be attributed to the local excited state, the intramolecular charge-transfer state, and the aggregation-induced emission state. The emission behaviors depend on which positions of the carborane are substituted. [ABSTRACT FROM AUTHOR]

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]

Flowerlike Bi2S3 microspheres have been successfully synthesized via a facile wet chemical route in air at 110 °C for 10 min, employing bismuth nitrate and thiourea in a molar ratio of 1 : 2 as the starting reactants, ethylene glycol as the reaction medium and polyvinylpyrrolidone (PVP) as the structure-directing reagent. Electron microscopy observations showed that the as-obtained product looked like an Asteraceae plant called Echinops Sphaerocephalus Linn in nature. The N2 sorption–desorption experiments showed that the Brunauer–Emmett–Teller (BET) area of the flowerlike microspheres was 32.4 m2 g−1. Some factors influencing the formation of flowerlike Bi2S3 microspheres were investigated, including the reaction temperature, and the sort and amount of the surfactant. The experiments showed that the Bi2S3 micro/nanostructures prepared in the present work could be used as new-type catalysts for the reduction of some aromatic nitro compounds, such as 4-nitroaniline, 2-nitrophenol and 4-nitrophenol. It was found that the as-obtained flowerlike Bi2S3 microspheres contributed to the best catalytic activity. [ABSTRACT FROM AUTHOR]

Electron accepting capability is greatly improved for B-phenylated tri-phenyl-o-carborane (1) through a favorable electronic interaction between the two adjoining phenyl-π* and cage carbon-σ* orbitals. [ABSTRACT FROM AUTHOR]

The incorporation of Sc 3+ can stabilize calcite-phase LuBO 3 :Ce 3+ 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)BO 3 :Ce was rapidly synthesized in batches via a high-throughput sol-gel method. The aliovalent substitution of Lu 3+ 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)BO 3 :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)BO 3 :Ce single crystals and thin films and their application in the scintillation field.

Conversion of carbon dioxide (CO 2 ) 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-CH 3 and UiO-68-OCH 3 , for the photocatalytic reduction of CO 2 . By introducing electron-withdrawing and electron-donating groups, UiO-68-PSMs showed different performance for the selective photocatalytic reduction of CO 2 to CO because of change in charge separation and band gap of UiO caused by the presence of different functional groups.

Facet-dependent catalytic activity of hard materials such as metals and metal oxides is well recognized in previous works. However, it has rarely been established for metal-organic frameworks (MOFs), possibly because the soft crystals of MOFs are conceptually different from the hard solids. In this work, the surface structure of the MOF NH 2 -MIL-125(Ti) has been investigated by density functional theory (DFT) calculations for the first time. These calculations predict that the {110} facet has a surface energy of 1.18 J m -2 , which is superior to those of the {001}, {100} and {111} facets. This difference can be attributed to the larger percentage of exposed metal clusters, which can act as active sites in catalysis. Thus, we have devised and successfully obtained a series of nanoscaled NH 2 -MIL-125(Ti) MOFs with controlled facets both experimentally and theoretically. The sample containing the {110} facet exhibits the highest photocatalytic hydrogen production activity and apparent quantum yield, which are approximately three times those of the sample with a dominant {111} facet.

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.

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 (5)D0→(7)F2 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.