Metal-Organic Frameworks for Greenhouse Gas Applications.

Using petrol to supply energy for a car or burning coal to heat a building generates plenty of greenhouse gas (GHG) emissions, including carbon dioxide (CO2 ), water vapor (H2 O), methane (CH4 ), nitrous oxide (N2 O), ozone (O3 ), fluorinated gases. These up-and-coming metal-organic frameworks (MOFs) are structurally endowed with rigid inorganic nodes and versatile organic linkers, which have been extensively used in the GHG-related applications to improve the lives and protect the environment. Porous MOF materials and their derivatives have been demonstrated to be competitive and promising candidates for GHG separation, storage and conversions as they shows facile preparation, large porosity, adjustable nanostructure, abundant topology, and tunable physicochemical property. Enormous progress has been made in GHG storage and separation intrinsically stemmed from the different interaction between guest molecule and host framework from MOF itself in the recent five years. Meanwhile, the use of porous MOF materials to transform GHG and the influence of external conditions on the adsorption performance of MOFs for GHG are also enclosed. In this review, it is also highlighted that the existing challenges and future directions are discussed and envisioned in the rational design, facile synthesis and comprehensive utilization of MOFs and their derivatives for practical applications.

Partially Oxidized Carbon Nanomaterials with Ni/NiO Heterostructures as Durable Glucose Sensors.

Conventional enzyme-based glucose biosensors have limited extensive applications in daily life because glucose oxidase is easily inactivated and is expensive. In this paper, we propose a strategy to prepare a new type of cost-effective, efficient, and robust nonenzymatic Ni-CNT-O for electrochemical glucose sensing. It is first followed by the pyrolysis of Ni-ABDC nanostrips using melamine to grow carbon nanotubes (CNTs) to give an intermediate product of Ni-CNT, which is further accompanied by partial oxidation to enable the facile formation of hierarchical carbon nanomaterials with improved hydrophilicity. A series of physicochemical characterizations have fully proved that Ni-CNT-O is a carbon-coated heterostructure of Ni and NiO nanoparticles embedded into coordination polymer-derived porous carbons. The obtained Ni-CNT-O exhibits a better electrocatalytic activity for glucose oxidation stemming from the synergistic effect of a metal element and a metal oxide than unoxidized Ni-CNT, which also shows high performance with a wide linear range from 1 to 3000 µM. It also offers a high sensitivity of 79.4 µA mM-1 cm-2, a low detection limit of 500 nM (S/N = 3), and a satisfactory long-term durability. Finally, this glucose sensor exhibits good reproducibility, high selectivity, as well as satisfactory results by comparing the current response of simulated serum within egg albumen.

Four new Mn(II) inorganic-organic hybrid frameworks with diverse inorganic magnetic chain's sequences: syntheses, structures, magnetic, NLO, and dielectric properties.

Four new inorganic-organic hybrid manganese frameworks, formulated as [Mn(Am-Hip)2]·3H2O (1), [Mn2(ip)2(H2O)]·CH3OH (2), [Mn2(OH-ip)2(DMF)]·DMF (3), and (Me2NH2)[Mn4(sdba)4(Hsdba)(H2O)]·3H2O·2DMF (4) (Am-H2ip = 5-aminoisophthalic acid, H2ip = isophthalic acid, OH-H2ip = 5-hydroxyisophthalic acid, and H2sdba = 4,4'-sulfonyldibenzoic acid), have been prepared by solvothermal reactions of Mn(II) ions with different polycarboxylate acids in the presence of LiNO3 or NH4NO3. Single-crystal X-ray diffraction studies reveal that the frameworks of 1-4 contain diverse Mn(II)-oxygen inorganic magnetic chain's sequences, -J1J1J1J1- for 1, -J1J2J1J2- for 2, -J1J1J2J2- for 3, and -J1J2J3J3- for 4. The sequence in 4 has never been seen for the magnetic chain compounds and is a new type of magnetic alternating sequence. Magnetic investigations indicate that these compounds all show weak antiferromagnetic couplings between the adjacent Mn(II) ions. Magnetostructural analyses based on the data of 1-4 and other related Mn(II) chain compounds imply that the magnitude of the magnetic coupling has some relationship with the Mn-O-Mn angle of the µ2-O bridge and the average Mn-O-C-O torsion angle of the carboxylate bridges. Compounds 2 and 4 crystallize in chiral and acentric space groups, and they both exhibit powder second harmonic generation (SHG) efficiencies approximately 0.6 and 0.9 times, respectively, that of the standard potassium dihydrogen phosphate (KDP) powder. In addition, the dielectric properties of 2 and 4 were also investigated.

Self-assembly of polyhedral indium-organic nanocages.

A synthetic strategy to construct discrete indium-organic polyhedra has been illustrated based on small three-membered windows from a 2,5-pyridinedicarboxylate (PDC) ligand with an angle of 120°. [Et2NH2]6[In6(PDC)12] (InOF-10) is a high-symmetry octahedron with eight three-membered windows, and [Et2NH2]18[In18(BPDC)6(PDC)30] (InOF-11) is a complex polyhedron derived from 3-edge-removed octahedra with an auxiliary biphenyl-3,3'-dicarboxylate (BPDC) ligand. Moreover, the sorption behavior of the latter is also well investigated.

The beneficial and toxic effects of selenium on zebrafish. A systematic review of the literature.

Selenium is an important and essential trace element in organisms, but its effects on organisms are also a "double-edged sword". Selenium deficiency or excess can endanger the health of humans and animals. In order to thoroughly understand the nutritional value and toxicity hazards of selenium, researchers have conducted many studies on the model animal zebrafish. However, there is a lack of induction and summary of relevant research on which selenium acts on zebrafish. This paper provides a review of the reported studies. Firstly, this article summarizes the benefits of selenium on zebrafish from three aspects: Promoting growth, Enhancing immune function and anti-tumor ability, Antagonizing some pollutants, such as mercury. Then, three aspects of selenium toxicity to zebrafish are introduced: nervous system and behavior, reproductive system and growth, and damage to some organs. This article also describes how different forms of selenium compounds have different effects on zebrafish health. Finally, prospects for future research directions are presented.

Highly thermostable mixed lanthanide organic frameworks with high quantum yield for warm white light-emitting diodes.

A mixed lanthanide organic framework was prepared via hydrothermal methods using m-phthalic acid (m-H2BDC), 1,10-phenanthroline (1,10-Phen), and Ln3+ ions, formulated as [HNMe2][Eu0.095Tb1.905(m-BDC)3(phen)2] (ZTU-6). The structure and stability of ZTU-6 were characterised by X-ray diffraction (XRD) and thermogravimetric analysis (TGA), which revealed a three-dimensional pcu topology with high thermal stability. Fluorescence tests showed that ZTU-6 emitted orange light with a high quantum yield of 79.15%, and it can be effectively encapsulated in a light-emitting diode (LED) device emitting orange light. In addition, ZTU-6 was found to be compatible with BaMgAl10O17:Eu2+ (BAM) blue powder and [(Sr,Ba)2SiO4:Eu2+] silicate yellow and green powder to create a warm white LED with a high colour rendering index (CRI) of 93.4, a correlated colour temperature (CCT) of 3908 K, and CIE coordinates of (0.38, 036).

Robust DUT-67 material for highly efficient removal of the Cr(VI) ion from an aqueous solution.

Robust DUT-67 was synthesized by the hydrothermal method and characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). To systematically study the removal of Cr(VI) ion by DUT-67, single-factor, competition ion, material regeneration, kinetic, and thermodynamic experiments were designed. The experimental results show that DUT-67 had a maximum removal rate of 96.1% and a maximum adsorption capacity of 105.42 mg g-1 with material regeneration and outstanding selective adsorption. In addition, the process of removal of the Cr(VI) ion from an aqueous solution by DUT-67, which accorded with the pseudo-second-order kinetics model and Langmuir model, was studied, and its adsorption mechanism was reasonably explained by the theoretical calculation.

Numerical hemolysis performance evaluation of a rotary blood pump under different speed modulation profiles.

Introduction: Speed modulation methods have been studied and even used clinically to create extra pulsation in the blood circulatory system with the assistance of a continuous flow rotary blood pump. However, fast speed variations may also increase the hemolysis potential inside the pump. Methods: This study investigates the hemolysis performance of a ventricular assist rotary blood pump under sinusoidal, square, and triangular wave speed modulation profiles using the computational fluid dynamics (CFD) method. The CFD boundary pressure conditions of the blood pump were obtained by combining simulations with the pump's mathematical model and a complete cardiovascular lumped parameter model. The hemolysis performance of the blood pump was quantified by the hemolysis index (HI) calculated from a Eulerian scalar transport equation. Results: The HI results were obtained and compared with a constant speed condition when the blood pump was run under three speed profiles. The speed modulations were revealed to slightly affect the pump hemolysis, and the hemolysis differences between the different speed modulation profiles were insignificant. Discussion: This study suggests that speed modulations could be a feasible way to improve the flow pulsatility of rotary blood pumps while not increasing the hemolysis performance.

Immobilization of iron phthalocyanine on MOF-derived N-doped carbon for promoting oxygen reduction in zinc-air battery.

Functional carbon nanomaterials play a crucial role in the cathodic oxygen reduction reaction (ORR) for sustainable fuel cells and metal-air batteries. In this study, we propose an effective approach to immobilize iron phthalocyanines (FePc) by employing a porous N-doped carbon material, denoted as NC-1000, derived from a sheet-shaped coordination polymer. The resulting NC-1000 possesses substantial porosity and abundant pore defects. The nitrogen sites within NC-1000 not only facilitate FePc adsorption but also optimize the electron distribution at the Fe-N site. The FePc@NC-1000 composite material exhibits a significant number of active centers in the form of Fe-N4 moieties, showcasing satisfactory ORR activity. Specifically, it demonstrates an onset potential of 0.99 V, a positive half-wave potential of 0.86 V, a large limiting current of 5.96 mA cm-2, and a small Tafel slope of 44.41 mV dec-1. Additionally, theoretical calculations and experimental results confirm the favorable performance and durability of zinc-air batteries assembled using FePc@NC-1000, thereby highlighting their considerable potential for practical applications. Overall, this study provides a comprehensive exploration of the enhanced catalytic performance and increased stability of metal-organic framework-derived functional carbon nanomaterials as cost-effective, efficient, and stable catalysts for the ORR.

MOF-on-MOF-Derived Hollow Co3 O4 /In2 O3 Nanostructure for Efficient Photocatalytic CO2 Reduction.

The photocatalytic transformation of carbon dioxide (CO2 ) into carbon-based fuels or chemicals using sustainable solar energy is considered an ideal strategy for simultaneously alleviating the energy shortage and environmental crises. However, owing to the low energy utilization of sunlight and inferior catalytic activity, the conversion efficiency of CO2 photoreduction is far from satisfactory. In this study, a MOF-derived hollow bimetallic oxide nanomaterial is prepared for the efficient photoreduction of CO2 . First, a unique ZIF-67-on-InOF-1 heterostructure is successfully obtained by growing a secondary Co-based ZIF-67 onto the initial InOF-1 nanorods. The corresponding hollow counterpart has a larger specific surface area after acid etching, and the oxidized bimetallic H-Co3 O4 /In2 O3 material exhibits abundant heterogeneous interfaces that expose more active sites. The energy band structure of H-Co3 O4 /In2 O3 corresponds well with the photosensitizer of [Ru(bpy)3 ]Cl2 , which results in a high CO yield of 4828 ± 570 µmol h-1  g-1 and stable activity over a consecutive of six runs, demonstrating adequate photocatalytic performance. This study demonstrates that the rational design of MOF-on-MOF heterostructures can completely exploit the synergistic effects between different components, which may be extended to other MOF-derived nanomaterials as promising catalysts for practical energy conversion and storage.

Strategies of strengthening mechanical properties in the osteoinductive calcium phosphate bioceramics.

Calcium phosphate (CaP) bioceramics are widely applied in the bone repairing field attributing to their excellent biological properties, especially osteoinductivity. However, their applications in load-bearing or segmental bone defects are severely restricted by the poor mechanical properties. It is generally considered that it is challenging to improve mechanical and biological properties of CaP bioceramics simultaneously. Up to now, various strategies have been developed to enhance mechanical strengths of CaP ceramics, the achievements in recent researches need to be urgently summarized. In this review, the effective and current means of enhancing mechanical properties of CaP ceramics were comprehensively summarized from the perspectives of fine-grain strengthening, second phase strengthening, and sintering process optimization. What's more, the further improvement of mechanical properties for CaP ceramics was prospectively proposed including heat treatment and biomimetic. Therefore, this review put forward the direction about how to compatibly improve mechanical properties of CaP ceramics, which can provide data and ideas for expanding the range of their clinical applications.

Preparation of Highly Stable DUT-52 Materials and Adsorption of Dichromate Ions in Aqueous Solution.

Highly stable DUT-52 materials were synthesized by the hydrothermal method and well-characterized by X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, and X-ray photoelectron spectroscopy (XPS). In order to systematically study the adsorption of dichromate ions in aqueous solution by the DUT-52 materials, a single factor experiment, kinetic experiment, thermodynamic experiment, competition ion experiment, and material regeneration experiment were designed. Based on the H-bond interaction between the dichromate ions and the H atoms of a NDC2- ligand, the DUT-52 materials showed a maximum removal rate of 96.4% and a maximum adsorption capacity of 120.68 mg·g-1 with excellent selective adsorption and material regeneration. In addition, the process of adsorption of dichromate ions by the DUT-52 materials is in accordance with the pseudo second-order kinetics and Langmuir models, and the adsorption mechanism and the important role of the H-bond interaction were reasonably explained using the XPS pattern and theoretical calculation. Accordingly, DUT-52 can be regarded as a multifunctional material for efficiently removing dichromate ions from the wastewater.

An Investigation on Fatigue Resistance of Notched Long Fiber-Reinforced Composite Materials.

A new type of specimen is proposed for further research on the structure of glass-fiber-reinforced resin matrix composite lamina, which holds the potential to significantly improve the fatigue property of materials while having limited effect on the tensile strength. Herein, the fatigue life, based on the monotonic tensile test, was simulated utilizing ANSYS and nCode analysis software. The results show that the tensile strength of the local notched fiber specimens is slightly lower than that of the continuous long-fiber specimens. However, when extending the notches' longitudinal distance, the impact to tensile strength becomes smaller and smaller. The results show that, when the longitudinal distance of the notched fiber is greater than 80 mm, the reduction in tensile strength is less than 0.65%. At the same time, the fatigue property of the specimens is improved considerably. It has been found in this experiment that when the notches' longitudinal distance is 100 mm, the notches' length is 1.5 mm, and the notches' width is 1.75 mm, the fatigue cycles number of the specimens reaches 126,000 cycles, which is about 180% higher than that of the 0-0 type long fiber specimens without notches. This investigation provides a robust foundation and is a compelling basis for further exploration of new fatigue specimens.

Hierarchical N-doped CNTs grafted onto MOF-derived porous carbon nanomaterials for efficient oxygen reduction.

The rational design and preparation of nonprecious metal-based oxygen reduction reaction (ORR) catalysts to facilitate electron and mass transport are of great significance in oxygen-involved energy applications. Herein, a stepwise approach to synthesize a type of hierarchically porous N-doped carbon nanotubes (CNTs) grafted onto zinc-based coordination polymer derived carbon nanomaterials (M-NCNT, M = Fe/Co/Ni) is proposed. At first, an isostructural zinc-based metal-organic framework (MOF) to HKUST-1(Cu) (ZnHKUST-1) is solvothermally prepared, and then under pyrolysis to obtain MOF-derived porous carbon. After the secondary calcination, the in-situ formed N-doped CNTs are efficiently catalyzed by iron group metal-based nanoparticles (Fe/Co/Ni), which are thermally reduced by porous carbon together with additional urea. The synergistic effect between ultrahigh porosity, large surface area, suitable N-doping, high graphitization degree, and ultrafine metal particles prompts M-NCNT series to exhibit satisfactory electrocatalysis in oxygen reduction. Among them, Fe-NCNT owns the optimal ORR activity with high positive onset potential (0.987 V), half-wave potential (0.860 V) and large diffusion-limited current density (4.893 mA cm-2). Meanwhile, it shows a high current retention of 90.7% after the 24-hour stability, and the obtained Zn-air battery by Fe-NCNT with open-circuit voltage of 1.44 V owns moderate capacity and satisfying stability. The demonstrated method to prepare hierarchically porous N-doped carbon nanomaterials stemmed from MOF precursors unfolds a new route for the facile construction of efficient nanocatalysts for advanced energy applications.

An efficient glucose sensor thermally calcined from copper-organic coordination cages.

Due to the harmfulness of diabetes, a fast and efficient glucose detector is particularly important. Metal-organic polyhedron (MOP) provides a porous framework and a special matrix, which makes it an excellent precursor for electrochemical detection. Herein, we report a novel MOP as a precursor for the preparation of an electrocatalytic detector for glucose. The new metal-organic polyhedron of Cu4(TPDC)4 can be solvothermally obtained and characterized by X-ray crystallography, which can be thermally converted into nanosized copper oxides embedded into graphitic carbon layers (MOP-CO). The as-prepared MOP-CO electrode is further applied to glucose detection, which shows a fast response time (<1 s) in a wide linear range of 0-4000 µM and high sensitivity of 2720 µA mM-1 cm-2, as well as low detection limit (26 nM (S/N = 3)), good anti-interference, repeatability and stability (>3600 s).

Bioinspired double self-adhesion coating based on dopamine, coating resin and phosphorylcholine for surface lubrication and antifouling functionalization.

Implanted medical devices that have poor friction property or biofilm formation can limit their service life and cause discomfort in patients. Recently, some zwitterionic coatings have been studied to modify the biomaterials surface for lubricating function, but the grafting methods of coatings are complicated and also seldom take the bacterial antiadhesion property into account at the same time. In our studies, motivated by the properties of nature mussels and human articular, we firstly successfully synthesized double adhesion protection of self-adhesive ternary polymer coating and achieved the excellent lubrication and antifouling functionalization of the medical devices surface. In details, the X-ray photoelectron spectroscopy, scanning electron microscope and the water contact angles could characterize the successful modification on the surface of titanium substrate. Additionally, the tribological tests carried out by atomic force microscope verified the ternary polymer could enhance the lubrication property owing to the hydration lubrication mechanism. Meanwhile, it also possessed the bacterial antiadhesion property for the initial 24 h attributed to the hydration repulsive force. We believe that, as a simple and universal preparation method, the ternary polymer could make a great significance for improving the surface function of biomaterials and alleviating patients' discomfort.

Zinc-tetracarboxylate framework material with nano-cages and one-dimensional channels for excellent selective and effective adsorption of methyl blue dye.

An example of a zinc-tetracarboxylate framework material (FJI-11) was solvothermally synthesized and structurally characterized. FJI-11 presented 3D cage-stacking frameworks with octahedral cages, cuboctahedral cages and two kinds of 1D channel along the c-axis. In addition, FJI-11 exhibited the excellent selective and effective adsorption of methyl blue (MB) dye by guest molecule exchange, and its adsorption process was in accordance with the second-order kinetic model and the Freundlich model.

A family of planar hexanuclear CoLn clusters with lucanidae-like arrangement and single-molecule magnet behavior.

A family of planar hexanuclear CoLn clusters with the hydroxyl and nitrogen rich ligand 2-[bis(pyridin-2-ylmethyl) amino]-2-(hydroxymethyl)propane-1,3-diol (H3L), formulated as [Co4Ln2(µ3-O)2(µ-N3)2(OH)2(H2O)2(HL)4]·(CH3CO2)2·20H2O [Ln = Dy (1), Gd (2), Tb (3), Eu (4) and Ho (5)], have been synthesized and structurally characterized. They are isomorphous and feature a lucanidae-like arrangement. They are the first examples of 3d-4f clusters with the H3L ligand. In addition, the magnetic properties of 1-5 have been investigated and the single-molecule magnet (SMM) behaviour is observed for 1.

A microporous MOF with open metal sites and Lewis basic sites for selective CO2 capture.

A robust indium-organic framework (InOF-15) with open metal sites and Lewis basic sites has been successfully synthesized using a quinoline-based dicarboxylic acid. Moreover, it exhibits high IAST selective CO2 sorption from CO2/CH4 and CO2/N2 mixtures at 273 K, which has been attributed to the coexistence of OMSs and LBSs with strong synergistic effects.

Anion dependent self-assembly of sandwich 13-metal Ni-Ln nanoclusters with a long-chain Schiff base ligand.

Two classes of Ni-Ln clusters [Ln4Ni3L3(OAc)6(NO3)3(OH)3] (Ln = Gd (1) and Tb (2)) and [Ln6Ni7L6(OAc)12(OH)6](OH)2 (Ln = Gd (3) and Dy (4)) were prepared using a specifically designed Schiff base ligand built around a flexible (CH2)2O(CH2)2O(CH2)2 chain. 1 and 2 exhibit cone-like structures, while 3 and 4 have nanosized sandwich architectures. The structures were studied by single-crystal X-ray diffraction and TEM, and magnetic properties were investigated.