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A Co–zeolite imidazole ester framework (ZIF-67) has excellent electrochemical performance for the oxygen reduction reaction (ORR), but the structural stability is still the key problem to be solved. PEDOT is a polymer of EDOT (3,4-ethylenedioxythiophene monomer), a π-conjugated conductive polymer with superior performance and wide application. It has a rigid and linear conformation, which is necessary to maintain the integrity of the material structure and prevent collapse. And this conformation is also conducive to charge transport and crystallization, resulting in good performance of high charge/discharge capacities, fast response time and high sensing ability. Herein through the pre-implantation of PEDOT nanowires, the structural collapse, anisotropic shrinkage and Co atom agglomeration of ZIF-67 in the pyrolysis process were inhibited, and S,N co-doping was realized at the same time. The XRD, SEM, TEM and XPS characterization studies prove that PEDOT nanowires successfully embedded in the ZIF-67 structure, and N and S are doped into the carbon framework of the catalyst. The synthesized catalyst has a regular hexahedral morphology, interconnected three-dimensional (3D) nanowire (NW) framework and graphitized carbon coated Co nanoparticles (Co/C@NS NWs), endowing it with excellent bifunctional catalytic performance toward oxygen. The initial potential was 0.91 V (vs. RHE) and the limiting current density was −4.8 mA cm−2 for the ORR. The potential required to reach 10 mA cm−2 is only 1.55 V (vs. RHE) and the Tafel slope for the oxygen evolution reaction (OER) is relatively low (100 mV dec−1). An open circuit voltage of 1.46 V for Zn–air battery cathodes catalyzed by Co/C@NS NWs at a discharge power density of 129.3 mWcm−2 is obtained, and the specific capacity at a discharge current density of 10 mA cm−1 is 800 mA h gZn−1. The voltages show no obvious change for a 35 h continuous discharge/charge cycle experiment. Therefore, this work provides a new inspiration for the design and development of high-performance non-noble metal carbon-based bifunctional oxygen electrocatalysts. [ABSTRACT FROM AUTHOR]

High-performance fluorescence sensors combining convenience, low cost and high sensitivity are prospective for water pollution and human health. Luminescent metal–organic frameworks (LMOFs) as sensors can meet these criteria for high efficient detection of toxic metal ions. Herein, a new LMOF LCU-109 has been fabricated by Sharpless in situ tetrazole synthesis system assisted by polycarboxylic O-donor ligand. It showed a 2D binodal (3,6)-connected kgd structure with multiple N and O dual-functional sites for detecting guest metal ions. As expected, LCU-109 can be highly sensitive and selectively detect trace amounts of Fe3+ and Cu2+ ions in an aqueous solution by the luminescence quenching mechanism. Notably, the detection limits (LODs) of Fe3+ and Cu2+ ions are 0.0043 and 0.0028 ppm, respectively, in water, which are significantly lower than the minimum standards stipulated for drinking water by the World Health Organization (WHO) (0.3/2.0 ppm) and U.S. Environmental Protection Agency (USEPA) (0.3/1.2 ppm). Moreover, LCU-109 also shows excellent luminescent sensing activities for Fe3+ and Cu2+ ions in simulated HEPES biological system and actual river water with low LODs of 0.034/0.019 ppm and 0.0756/0.107 ppm, respectively, which is also lower than the standard of WHO and USEPA. Moreover, convenient and real-time naked eye detection effects are provided by the exquisitely made LCU-109 fluorescent test papers. Importantly, combining density functional theory (DFT) calculations with a variety of experiments, the fluorescence quenching mechanism for energy competitive absorption and weak interaction is further revealed. [ABSTRACT FROM AUTHOR]

para-Selective hydroxylation of alkyl aryl ethers is established, which proceeds with a ruthenium(II) catalyst, hypervalent iodine(III) and trifluoroacetic anhydride via a radical mechanism. This protocol tolerates a wide scope of substrates and provides a facile and efficient method for preparing clinical drugs monobenzone and pramocaine on a gram scale. [ABSTRACT FROM AUTHOR]

High-performance electromagnetic interference (EMI) shielding materials that are effective under a wide range of conditions are highly attractive for eliminating electromagnetic pollution in fifth-generation communication. Here, we report a sandwich-layered hybrid film (12 μm) constructed by multi-walled carbon nanotubes (MWCNTs) and silver nanowires (Ag NWs) via vacuum-assisted filtration. In the ultra-wideband (4–40 GHz), the EMI shielding effectiveness (EMI SE) was higher than 45 dB with a maximum of 72 dB at 10 GHz. This superb EMI SE can be attributed to the design of the alternating Ag NW/MWCNT structure, in which the Ag NWs with high conductivity provide ohmic loss, and the MWCNTs with abundant defects induce polarization loss. Such a structure improves impedance matching through the top layer of the MWCNTs and enhances multiply reflected absorption by the macroscopic interface between the MWCNT layer and the Ag NW layer. Moreover, DFT calculations verified that the existence of an Ag/C micro-interface caused uneven distribution of charges, which contributed to dipole polarization. Considering practical applications, the film maintained superior EMI SE under complex environments (hot, cold, and bending) and exhibited excellent heat dissipation properties. This work facilitates the further development of super-wideband EMI shielding materials for broad applications. [ABSTRACT FROM AUTHOR]

Adsorptive separation of physically and chemically similar molecules and understanding the underlying host–guest interactions at the molecular level are of significant scientific and practical importance. Here we report the development of a novel calcium-based metal–organic framework, formulated as Ca3(Htcpp)2 (H4tcpp = 2,3,5,6-tetrakis(4-carboxyphenyl)-pyrazine) featuring microporosity and high stability. This compound shows distinct adsorption behavior toward xylene isomers and is capable of separating them efficiently at an industrially relevant temperature. The selective adsorption is attributed to a synergetic thermodynamic and kinetic effect. The host–guest interactions were probed directly by single-crystal X-ray diffraction analysis and the adsorption affinity was evaluated through computational molecular simulations. [ABSTRACT FROM AUTHOR]

A practical electrophilic aminoselenation of O-homoallyl benzimidate with diselenides promoted by PhICl2/Cu2O has been developed. The easily available and stable diselenides were used as selenium sources. Various selenyl 1,3-oxazines, which are important frameworks in medicinal and biological chemistry, were easily obtained in moderate to good yields for the first time. Easy scaleup and scalability make this method attractive for the preparation of other valuable organoselenides. [ABSTRACT FROM AUTHOR]

Macrocyclic host molecules play the central role in host–guest chemistry and supramolecular chemistry. The highly structural symmetry of macrocyclic host molecules can meet people's pursuit of aesthetics in molecular design, and generally means a balance of design, synthesis, properties and applications. For macrocyclic host molecules with highly symmetrical structures, building blocks, which could be described as repeat units as well, are the most fundamental elements for molecular design. The structural features and recognition ability of macrocyclic host molecules are determined by the building blocks and their connection patterns. Using different building blocks, different macrocyclic host molecules could be designed and synthesized. With decades of developments of host–guest chemistry and supramolecular chemistry, diverse macrocyclic host molecules with different building blocks have been designed and synthesized. Aromatic building blocks are a big family among the various building blocks used in constructing macrocyclic host molecules. In this feature article, the recent developments of macrocyclic host molecules with aromatic building blocks were summarized and discussed. [ABSTRACT FROM AUTHOR]

Ferroelectric films can sustain large strain induced by substrate constraints, which may additionally modulate their crystal structures and electrical properties. This study revealed the strain engineering effect on the piezoelectricity of (100-x)%Bi1/2Na1/2TiO3-x%BaTiO3 (BNT-BTx) epitaxial films grown on Nb:SrTiO3100 (NSTO100) substrates in association with the crystal structure affected by film thickness. Several compositions in the BNT-BTx system, i.e. BNT-BT2, BNT-BT6 and BNT-BT15, were studied as typical representatives of ferroelectric rhombohedral, relaxor ferroelectric pseudo-cubic (near morphotropic phase boundary) and ferroelectric tetragonal structures, respectively. It was found that a monoclinic–rhombohedral phase transition appeared in BNT-BT2 films when we changed the film thickness, which was caused by the coherent strain imposed by the substrates. The 3-layer BNT-BT2 film (∼150 nm) exhibited a phase coexistence of monoclinic and rhombohedral phases, so that the effective piezoelectric constant was enhanced by at least 260% compared to films with pure monoclinic or rhombohedral phases. The present work may offer a feasible way to improve the piezoelectric properties of other perovskite piezoelectric films. [ABSTRACT FROM AUTHOR]

Herein, (NH4)2V7O16 hierarchical structures formed by the self-assembly of nanoflakes were successfully synthesized by a one-step rotating hydrothermal method. When utilized as anodic materials for aqueous Li-ion batteries, the obtained (NH4)2V7O16 exhibited good rate capability and excellent cyclic stability. Moreover, the structural evolution of the ammonium vanadium bronze during cycling was also investigated by ex situ XRD. [ABSTRACT FROM AUTHOR]

This paper reports two closely related heteropentanuclear manganese complexes, namely, {Na2Mn3(opch)3(μ4-O)(μ2-N3) (μ2-AcO)(μ2-MeO)}·6CH3OH·0.5H2O (1) and {Na2Mn3(opch)3(μ4-O)(μ2-N3)2(μ2-AcO)}·2.5CH3OH·2H2O (2), where H2opch is (E)-N′-(2-hydroxy-3-methoxybenzylidene)pyrazine-2-carbohydrazide. Single-crystal X-ray diffraction analysis reveals that the trigonal bipyramidal skeletons in both complexes are comparable, where a perfect triangular Mn3 motif occupies the equatorial plane. Magnetic investigations suggest that overall antiferromagnetic coupling is present within the triangles of 1 and 2. However, their dynamic magnetic properties are drastically distinct. Indeed, complexes 1 and 2 show two kinds of dual slow magnetic relaxation processes that correspond to anisotropy barriers (Δ) of 9.2 cm−1 (11.4 cm−1 for 2) and 12.8 cm−1 (30.0 cm−1 for 2) for the low- and high-frequency domains, respectively. More importantly, a further comparative study of the structure and magnetism indicates that the coordination sphere of these two model complexes with the homologous hydrazone-based coordination sites undergoes an alteration from methoxide-O to azide-N upon a subtle change of the auxiliary anion accompanied by modulating octahedron geometries, leading to a further influence on different relaxation dynamics. [ABSTRACT FROM AUTHOR]

Transfer hydrogenation of nitroarenes to the corresponding anilines using hydrazine hydrate and non-noble metal catalysts has already been widely studied. However, the toxicity resulting from excess hydrazine hydrate and the high reaction temperature limit its industrial application. Herein, a novel N-doped molybdenum oxide compound (Mo4O4N3) was in situ prepared from g-C3N4 and (NH4)6Mo7O24·4H2O (AHM). The as-prepared Mo4O4N3 can achieve a 99% yield of aniline using a stoichiometric molar ratio of hydrazine hydrate (–NO2 : N2H4·H2O = 1 : 1.5) at room temperature for 50 minutes. Mechanistic experiments and characterization techniques indicate that the acidic sites of unsaturated Mo in Mo4O4N3 can efficiently activate N2H4 molecules to form active hydrogen species for catalytic transfer hydrogenation of nitroarenes without the generation of hazardous NH3. Besides, Mo4O4N3 still exhibited excellent catalytic performance for the large-scale reaction without solvent. This work may offer a feasible and efficient strategy for arylamine production. [ABSTRACT FROM AUTHOR]

The separation of alkane/alkene gas mixtures represents an important yet challenging process in the petrochemical industry to produce valuable chemical feedstocks with sufficiently high purity. These molecules have similar physical properties, making their separation difficult and capital-intensive. The current separation and purification technology relies largely on heat-driven distillations with a huge unit composed of hundreds of trays. Adsorptive separation using porous solids is capable of accomplishing the purification under ambient conditions, offering potential energy and environmental benefits. In particular, metal–organic frameworks (MOFs) hold enormous promise for this separation process in light of their highly tunable pore shape, pore size, and pore surface functionality. In this review article, we provide a comprehensive account of metal–organic frameworks that have been investigated for the separation of alkanes and alkenes with a focus on C2–C3 hydrocarbons. The material design rationale, separation mechanisms, and structure–property relations are highlighted. Finally, the existing challenges and possible design strategies for desirable materials are also discussed. [ABSTRACT FROM AUTHOR]

The synthesis conditions of most phosphors doped with lanthanide ions with d–f transition require a reducing atmosphere. The doping Bi3+ ions selected in this study perfectly avoid this requirement, and they are environmentally friendly and safe. Nevertheless, the spectral tuning of Bi3+ is a great challenge that limits its application. Herein, by regulating the value of x in the new solid solution Sr2+xLa1−xGaO5−xFx, the luminescence of Bi3+ is well promoted. Through an excitation-driven strategy, the emission peak position of Bi3+ is redshifted, and the luminescence of trivalent bismuth is successfully adjusted, which can also be applied to anti-blue lighting. In addition, we constructed a Bi3+–Eu3+ dual luminescence system, and, regardless of changes in the Bi3+/Eu3+ concentration or excitation wavelength, a single matrix white light phosphor was realized. Through calculations, the activation energy of the phosphor doped with 2.5%Eu3+ was found to be 0.257 eV, which is higher than the activation energy of some common compounds. This indicates that the phosphor has good application prospects in the field of solid-state lighting. It is worth noting that based on the different thermal response behaviors of Bi3+ and Eu3+, when the Eu3+ content is fixed at 1%, the maximum relative sensitivity of the optical thermometer based on its fluorescence intensity ratio is about 1.46% K−1 at 383 K, which is higher than that of Bi3+ and Eu3+ co-doped phosphors previously reported. We also obtained a high absolute sensitivity of 0.00139 K−1 at 403 K. Therefore, we also studied the thermal sensitivity of Bi3+ and Er3+ co-doped solid solutions. The results show that this solid-solution phosphor has far-reaching application prospects in the temperature sensing field. [ABSTRACT FROM AUTHOR]

Monitoring the concentration of dopamine (DA) is vital for preventing and diagnosing DA related diseases. In contrast to the traditional sensing methods for DA, in which direct or indirect effects on the optical probes are often recorded, a novel sensing concept is disclosed based on as a result of the in situ formation of polydopamine (PDA) originating from the synergetic effect between boron nitride quantum dots (BNQDs) and Cu2+. In the co-presence of BNQDs and Cu2+, DA was catalytically oxidized to PDA, accompanied by an obvious color change from colorless to brown. In contrast to previous reports, in which BNQDs have been employed as an optical probe, herein, the BNQDs not only acted as the optical energy donor, but also as the catalysts for the formation of PDA. The quenching efficiency resulting from the inner filter effect and the electron transfer between the BNQDs and PDA was directly proportional to the concentration of DA, ranging linearly from 2 to 80 μM with a limit of detection of 0.49 μM. The present system exhibited an outstanding selectivity for DA among other interfering coexisting biomolecules. Furthermore, the practical application of the proposed platform was verified by assaying DA in human plasma samples, and satisfactory recoveries ranging from 101.24% to 111.98% were obtained. With the satisfactory reliability, repeatability and stability, the proposed simple sensor showed significant potential for use in DA detection in other biomedical applications. [ABSTRACT FROM AUTHOR]

Laser-induced breakdown spectroscopy (LIBS) experiments were carried out with an ammonium dinitramide (ADN)-based propellant to measure its distribution, that is the mixture ratio, in an inert atmosphere. A heating sampler was developed to produce a premixed sample with a known mixture ratio and this was connected to a chamber that had been designed to simulate the space propulsion environment. Determining the time window for the acquisition and saturation threshold of LIBS were the main motivations to investigate the effective lifetimes of atomic spectral lines and the effect of laser energy on the emission ratio. From the spectroscopic analysis, it was found that the ratio of the intensities of H (656.3 nm), O (777 nm) and N (746.8 nm) over Ar (738.4 nm) increased monotonically with the mixture ratio in the range of 0–0.06. A series of propellant/Ar mixtures with a pressure in the region of 40–100 kPa were used to obtain a linear correlation between the intensity ratio of LIBS spectra and the local mixture ratio. It was observed that the logarithm of the slope of the lines also showed a linear correlation with the pressure. Considering that the current method was applied by necessity with the given pressure, the local pressure was studied based on its dependence on the full width at half maximum (FWHM) of H and Ar spectral lines. Consequently, the emission ratios of H/Ar, O/Ar and N/Ar were utilized as a diagnostic tool to obtain the distribution of the propellant in the inert atmosphere. The LIBS-based results not only provide fundamental data for the on-line measurements of ADN-based thrusters, but also hold promise for promoting the application of LIBS in the field of energetic ionic liquids. [ABSTRACT FROM AUTHOR]

Three polymer donors named Qx-8F, Qx-10F, and Qx-12F, with similar chemical structures, were synthesized. The energy level of these donors is manipulated by precisely controlling the fluorination sites. We demonstrate that the exciton dissociation efficiency is gradually enhanced from Qx-8F:Y6 to Qx-12F:Y6, leading to improved open circuit voltage VOC and short circuit current density JSC for donors with a higher degree of fluorination. Simultaneously, the trap-assisted recombination or bimolecular recombination intensity is reduced, while the extraction rate is enhanced because of increased charge carrier mobilities, leading to an increase in fill factor for donors with higher amount of fluorine atoms. The optimized device based on Qx-12F with the most fluorine atoms and the non-fullerene acceptor Y6 shows the highest power conversion efficiency of 15.21%, with a VOC of 0.85 V, JSC of 24.55 mA cm−2, and fill factor of 72.88%. It is further demonstrated that the optimized ternary device based on the Qx-12F:PM6:Y6 blend provides a power conversion efficiency of 16.32%. [ABSTRACT FROM AUTHOR]

Heterostructural engineering and noble metal coupling are effective strategies to optimize semiconductor photocatalytic materials. In this work, (Ag, Mn2O3)-codecorated ZnO nanoparticles with different Mn2O3 contents (0–10 mol%) were synthesized by integrating the two strategies by a facile two-step polymer network-gel process. The photocatalytic activity of Ag/ZnO (AZM0) was significantly enhanced with the optimum Mn2O3 molar ratio of 3 mol%. The degradation efficiency of AZM3 is ∼3 times and ∼4.8 times higher than that of AZM0 for the degradation of methylene blue (MB) upon exposure to simulated sunlight and visible light, respectively. Also, this ternary nanocomposite exhibits enhanced gas sensing performance towards NO2 under ultraviolet/visible light irradiation at room temperature. The analysis of its microstructural, optical and photoelectrical characteristics suggests the synergistic coupling effects of Ag and Mn2O3, in which the significantly enhanced visible light response and hetero-interface charge carrier migration are the critical factors for the improvement of photocatalytic efficiency and gas sensing activity. Furthermore, the effects of recycling ability, the influence of the initial solution pH, the catalyst dosage and the main active species during the catalysis process on photocatalytic activity were explored. This study develops a feasible pathway to consciously construct multiheterostructures for enhancing the photocatalytic activity with great potential applications in toxic pollution abatement and noxious gas detection. [ABSTRACT FROM AUTHOR]

This study describes a novel antibacterial phototherapeutic platform for highly efficient healing of bacteria-infected wounds. It is based on the photodynamic and physical actions of a zinc tetraaminophthalocyanine-modified graphene oxide nanocomposite produced via non-covalent functionalization. The nanocomposite is positively charged and can easily capture negatively charged bacteria via electrostatic interactions. The antibacterial action is two-fold: (1) reactive oxygen species are produced by the phthalocyanine photosensitizer after short-term exposure to 680 nm light and (2) the graphene oxide can physically cut bacterial cell membranes. These enhanced activities can kill Gram-positive and Gram-negative bacteria at very low dosages. An ultrastructural examination indicates that this nanocomposite causes enormous damage to bacterial morphology and leakage of intracellular substances that lead to bacterial death. A rat wound model is used to demonstrate that the proposed phototherapeutic platform has low cytotoxicity and can promote rapid healing in bacteria-infected wounds. These results suggest that the integration of different antibacterial methods into a single nanotherapeutic platform is a promising strategy for anti-infective treatment. [ABSTRACT FROM AUTHOR]

Due to the incorporation of gold nanoparticles (AuNPs), previously reported AuNP-based FRET nanoflares still have some problems, such as non-negligible cytotoxicity and a time-consuming preparation procedure. In this communication, a novel AuNP-free FRET nanoflare for intracellular ATP imaging is developed based on a DNA nanostructure, which is self-assembled through cyclic U-type hybridization only involving a certain number of DNA strands. [ABSTRACT FROM AUTHOR]

A "superaerophobic" NiCo bimetallic phosphide electrocatalyst has been fabricated by employing bimetal–organic frameworks as self-sacrificing templates. An overpotential of only 205 mV can drive the HER current density to 800 mA cm−2, which is even superior to that for Pt/C. This study provides a promising approach for the development of industrialized HER electrocatalysts. [ABSTRACT FROM AUTHOR]

A photochemical method is used to grow Au nanoplates in high yield from in situ generated Au cluster seeds through the galvanic replacement reaction. The morphology of nanoplates can be further controllably tuned by adjusting the pH, and enhanced morphology determined non-linear optics performances are obtained. [ABSTRACT FROM AUTHOR]

In this paper, a series of Eu3+/Tb3+ doped La3Ga5SiO14 (LGS:Eu3+, Tb3+) phosphors with excellent performance have been synthesized by high-temperature solid-phase method. The effects of Eu3+ and Tb3+ doping in LGS on the host lattice were analyzed by X-ray diffraction (XRD). X-ray photoelectron spectroscopy (XPS) proved that the Eu3+ and Tb3+ ions were successfully doped into the LGS host. The doped Eu3+/Tb3+ ions only occupy the eight-coordinated La3+ sites. The concentration quenching points of LGS:Eu3+ and LGS:Tb3+ phosphors were determined to be 0.16 and 0.18, respectively. The luminescence performance and fluorescence lifetime of LGS:Eu3+, Tb3+ were studied. LGS:Eu3+, Tb3+ phosphors successfully realized Tb3+ → Eu3+ energy transfer to enhance Eu3+ luminescence. The energy transfer mechanism is speculated on using the experimental results. The energy transfer efficiency from Tb3+ to Eu3+ is about 66.83% in La2.46Tb0.18Eu0.36Ga5SiO14. The LGS:Eu3+, Tb3+ phosphors can achieve tunable luminescence by controlling the doping concentrations of Eu3+ and Tb3+. The ΔE is calculated to be 0.2567 eV for the La2.70Eu0.12Tb0.18Ga5SiO14 phosphor. [ABSTRACT FROM AUTHOR]

Volatile aldehydes cause great harm to human health and the living environment, and the detection of aldehydes has attracted much attention from chemists and material scientists. In recent years, as one of the most promising classes of functional materials, luminescent metal–organic frameworks (LMOFs) have bloomed as fluorescent sensors for the detection of aldehydes. Herein, the sensing properties of LMOF sensors toward formaldehyde, benzaldehyde, acetaldehyde and other aldehydes have been reviewed, and the sensing mechanism and applications are also illustrated. Additionally, the current status and its potential development prospects in this field are outlined. [ABSTRACT FROM AUTHOR]

Most praseodymium-doped red-emitting phosphors need high-temperature synthesis conditions with a reducing atmosphere. The niobate matrix selected in this work provides a sufficient electron-rich-site environment for praseodymium through charge migration, and praseodymium can be self-reduced in air atmosphere, which is safe and environmentally friendly. By building the [NbO6] group → Pr3+ energy transfer and finely modifying the doping concentration of Pr3+ ions, we constructed a dual-luminescence-system of the [NbO6] group and Pr3+. Thereby, optical temperature measurement based on fluorescence intensity ratio (FIR) technology of Pr3+ ions and [NbO6] groups was carried out using non-thermal coupling pairs, through the Boltzmann fitting and integral calculation, the maximum Sr and Sa values were 2.25% K−1 and 0.0049 K−1 at 403 K and 443 K, respectively, the Sr value is four times that obtained from the thermal coupling of Pr3+ ions, which exceeded most values previously reported for the fluorescence powder. Accordingly, we also studied the thermal sensitivity of Er3+ ions and Eu3+ ions mono-doped CaNb2O6 substrates. Results reveal that CaNb2O6:Pr3+/Er3+/Eu3+ phosphors have splendid temperature sensitivity and have far-reaching application prospects in the field of temperature measurements. [ABSTRACT FROM AUTHOR]

Here, using three metal cations (Mg2+, Al3+, and Zr4+) and an excited-state intramolecular proton transfer (ESIPT) active linker, 2,5-dihydroxyterephthalic acid (H2DHT), three luminescent metal–organic frameworks (LMOFs) were obtained. Importantly, their ESIPT-based luminescence originated from the linker was systematically tuned in emission profiles including intensity, emission color, and quantum efficiency in the solution as well as in the solid state, which is largely dependent on the composition and structural characteristics of these three LMOFs. Similar to the free linker, the Mg-based MOF possesses a relatively strong luminescence, the Al-based MOF has moderate luminescence due to the breathing effect, and the Zr-based MOF is very weakly luminescent, mainly caused by the LMCT process. Benefiting from unique emission behaviors of these three LMOFs, we further modulated their ESIPT-based luminescence through the interplay between guest species and components of LMOFs by combining with various photophysical processes, and successfully explored their potential applications as versatile photoluminescent platforms for target-triggered sensory materials, responsive fluorescent hydrogels, and white-light-emitting phosphors. [ABSTRACT FROM AUTHOR]

Microwave assisted lignin depolymerization was investigated over HSZ-supported CuNiAl-based catalysts. The synergistic effect between the acidic HSZ support and mixed metal oxides was studied in detail to explore the difference in catalytic activity during the lignin depolymerization process. Improvements in bio-oil properties, such as the H/C ratio and HHV value, were observed in comparison with raw lignin under rather mild conditions (140 °C, 80 min) in the absence of external hydrogen. The molecular weight of bio-oil obtained over HSZ-supported catalysts decreased, indicating that the increased acidity in the catalyst could facilitate microwave assisted lignin depolymerization. The product distributions in bio-oil were also analyzed and plausible depolymerization mechanisms were proposed considering the distributions of lignin-derived dimers/trimers and monomers. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis (UC), is a chronic disease characterized by diffuse mucosal inflammation limited to the colon. Topical drug delivery systems that could be facilely performed and efficiently retained at colon sites are attractive for clinical IBD treatment. Herein, we report the exploration of an injectable thermosensitive copolymer hydrogel as a topical formulation for IBD treatment and demonstrate its feasibility in UC treatment by shielding ulcer sites from the external environment and being a drug reservoir for sustained release. Poly(aliphatic ester)-based triblock copolymer, poly(DL -lactic acid)–poly(ethylene glycol)–poly(DL -lactic acid) (PDLLA–PEG–PDLLA), adopts the solution state at room temperature yet a gel state at body temperature when the polymer concentration is more than 11%. The gel acts not only as a physical mucosal barrier for protecting ulcer sites from microorganisms like bacteria but also as a mesalazine depot for enhanced drug retention in the colon for localized, sustained drug release. In vivo UC treatment reveals that blank gel as a mucosal protector shows nearly the same treatment effect to mesalazine SR granules. Mesalazine-loaded gel significantly suppresses inflammation and has the best outcomes of indices such as colonic length, mucosal injury index, pathological tissue, and inflammatory factor. The injectable thermosensitive polymer hydrogel represents a novel, robust platform for the efficient treatment of IBD by acting as a physical shield to block out the pro-inflammatory factors as well as a drug depot for enhanced drug retention and controlled delivery. [ABSTRACT FROM AUTHOR]

The Li–O2 battery is recognized as one of the most promising energy storage devices for next-generation automotive batteries due to its extremely high theoretical energy density. The design and preparation of highly active and durable catalysts for the air cathode are vital to make its practical application possible. Herein, we present a well-designed graphene-based cathode material in which single Co atoms are coordinated with N in three-dimensional reduced graphene oxide and Ru clusters are anchored on the surface of the material. The battery with our optimal sample (RuNC/CoSA–3DNG) as the cathode exhibits a discharge capacity of 25 632 mA h g−1 (at 100 mA g−1) and superior cycling stability for 300 cycles. The greatly enhanced performance is attributable to the highly active Co–N–C sites and the electron-deficient Ru nanoclusters, which facilitate increased ORR/OER activity and higher Ru atomic utilization efficiency. This work may provide new inspiration for designing highly efficient catalysts for Li–O2 batteries. [ABSTRACT FROM AUTHOR]

Amide linkage of glycine–amino acid was synthesized by coupling of substituted 2-(aminomethyl)malononitrile as a C-terminal glycine unit and N-terminal amine using CsOAc and O2 in an aqueous solution. This is a coupling reagent-free and catalyst-free peptide synthesis via oxidative amide bond formation. Various tripeptides and tetrapeptides were synthesized efficiently and the sulfide moiety is inert even under an oxygen atmosphere. [ABSTRACT FROM AUTHOR]

A bimodal-pore strategy was developed for preparation of the Pt3Co/C catalyst with active Pt3Co nanoparticles located around the mass transfer channels rather than inside them, which leads to ca. 29% higher mass transfer efficiency and a superior single-cell performance under an ultralow Pt loading. [ABSTRACT FROM AUTHOR]

Detailed photophysical processes of two AuCu14 clusters with different substituents (–F or –C(CH3)3) of the thiol ligand were studied in this work. The electronic effect of the substituents led to structural shrinkage, thus enhancing the luminous intensity. The internal conversion (IC) and intersystem crossing (ISC) rates in the AuCu14-C(CH3)3 crystal were slower compared with the AuCu14-F crystal, which was caused by the steric effect. [ABSTRACT FROM AUTHOR]