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An unprecedented photocatalyst, Sm2EuSbO7, was successfully fabricated in this paper, through a high-temperature solid-state calcination method, which represented its first ever synthesis. Additionally, using the solvothermal method, the Sm2EuSbO7/ZnBiSbO5 heterojunction photocatalyst (SZHP) was fabricated, marking its debut in this study. XRD analysis confirmed that both Sm2EuSbO7 and ZnBiSbO5 exhibited pyrochlore-type crystal structures with a cubic lattice, belonging to the Fd3m space group. The crystal cell parameter was determined to be 10.5682 Å or 10.2943 Å for Sm2EuSbO7 or ZnBiSbO5, respectively. The band gap width measured for Sm2EuSbO7 or ZnBiSbO5 was 2.73 eV or 2.61 eV, respectively. Under visible light irradiation for 150 min (VLTI-150 min), SZHP exhibited remarkable photocatalytic activity, achieving 100% removal of parathion methyl (PM) concentration and 99.45% removal of total organic carbon (TOC) concentration. The kinetic constant (k) for PM degradation and visible light illumination treatment was determined to be 0.0206 min−1, with a similar constant k of 0.0202 min−1 observed for TOC degradation. Remarkably, SZHP exhibited superior PM removal rates compared with Sm2EuSbO7, ZnBiSbO5, or N-doped TiO2 photocatalyst, accompanied by removal rates 1.09 times, 1.20 times, or 2.38 times higher, respectively. Furthermore, the study investigated the oxidizing capability of free radicals through the use of trapping agents. The results showed that hydroxyl radicals had the strongest oxidative capability, followed by superoxide anions and holes. These findings provide a solid scientific foundation for future research and development of efficient heterojunction compound catalysts. [ABSTRACT FROM AUTHOR]

With the purpose of enhancing the photocatalytic activity of titania (TiO2) coatings with low cost, a method of sulfuric-acid-bath pretreatment followed by simple oxidation in air has been proposed to fabricate TiO2 coatings. The effect of oxidation temperature on the crystal structure, surface morphologies and photocatalytic activity of TiO2 coatings was investigated, to figure out the suitable oxidation temperature. XRD and Raman's results show that the phase transformation of TiO2 starts at 773 K. The surface morphologies of TiO2 coatings clearly show the porous-like structure at lower than 873 K. With raising the temperature, the photocatalytic activity of TiO2 coatings firstly increases, then decreases, and reaches the highest at relatively low oxidation temperature of 773 K. [ABSTRACT FROM AUTHOR]

Black photocatalyst coatings of 6-potassium titanate (K 2 Ti 6 O 13 ) and anatase TiO 2 were formed on the surface of TiC coatings by low-temperature heat treatment in molten salt of KNO 3 at 673 K for 3 h. The surface of the composite coatings of K 2 Ti 6 O 13 -TiO 2 /TiC shows the nano-sheet flower-like structure, which could substantially increase the accessible surface area, compared with that of composite coatings of K 2 Ti 6 O 13 /Ti by the same treatment for Ti coatings. The composite coatings of K 2 Ti 6 O 13 -TiO 2 /TiC obtain high and stable adsorption, and still show photocatalytic activity. The results show that the low-temperature treatment in molten salt is a simple and effective approach to fabricate catalyst with nano-sheet K 2 Ti 6 O 13 . [ABSTRACT FROM AUTHOR]

An inexpensive and effective method is used to enhance the photocatalytic activity of photocatalyst coatings by heat treatment in carbon atmosphere. Nano-bump structure with mixed crystal of titanium oxycarbide and rutile TiO 2 form on the surface of Ti coatings, during heat treatment in carbon atmosphere. In the case of heat treatment in air, micro-column structure with rutile TiO 2 form on the surface of Ti coatings. The change of surface morphologies substantially increases the accessible surface area. During heat treatment in carbon atmosphere, oxygen vacancies generated in the lattice of mixed crystal are in favor of narrowing band gap. The narrowed band gap effectively benefits the generation of more photo-induced electrons and holes to enhance the photocatalytic activity under both ultraviolet and visible-light irradiation, compared with the pristine TiO 2 coatings. [ABSTRACT FROM AUTHOR]

This study thoroughly investigated the microstructure and mechanical properties of AlSi10Mg periodic cellular lattice structures with a wide range of volume fractions (5–20%) and unit cell sizes (3–7 mm) fabricated via direct metal laser sintering (DMLS). It was found that the arc-shaped melt pools are overlapping with each other and comprising near fully dense struts (relative densities≥99%) of the as-built lattice structures. The melt pools of the struts are characterized with very fine cellular-dendritic microstructure. Two distinctive zones in the melt pool can be distinguished: the boundary of melt pool possesses the coarse cellular/dendritic microstructure with the cell size or dendrite arm spacing ranging of 2–4 µm, while the interior of melt pool exhibits the much finer cellular microstructure consisting of the 400–700 nm cells mainly filled with the α-Al matrix and some embedded rod-type Si-phases, and the network boundaries predominantly generated by the aggregates of approximately 20 nm Si particles. Both compression strength and microhardness decrease with the increase in the unit cell size when the volume fraction is fixed. This is mainly because the thinner struts of the smaller unit cell size lattice structures were cooled faster by their surroundings and then exhibit a higher cooling rate, leading to finer microstructure. The compression strength increases with increasing the volume fraction, and an equation based on the Gibson–Ashby model is established to estimate the compression strength of DMLS-produced AlSi10Mg gyroid cellular lattice structures with the 3 mm unit cell size. [ABSTRACT FROM AUTHOR]

Highlights: [•] A unique cell type called gyroid is designed to construct lattice structures. [•] Curved cell surface as a self-supported feature avoids support structures. [•] Lattice structures with a wide volume fraction range were made. [•] Lattice structures were made at different orientations. [•] Strength and modulus increase with the increase in the volume fraction. [ABSTRACT FROM AUTHOR]

Abstract: Metallic additive manufacturing techniques, in particular the selective laser melting (SLM) process, are capable of fabricating strong, lightweight and complex metallic lattice structures. However, they still face certain process limitations such as geometrical constraints and in some cases the need for support structures. This study evaluates the manufacturability and performance of SLM produced periodic cellular lattice structures, which are designed by repeating a unit cell type called gyroid consisting of circular struts and a spherical core. The effect of unit cell size on the manufacturability, density and compression properties of the manufactured cellular lattice structures were investigated. Micro-computer tomography (CT) scan results reveal that the gyroid cellular lattice structures with various unit cell sizes ranging from 2 to 8mm can be manufactured free of defects by the SLM process without the need of additional support structures. The Scanning Electron Microscope (SEM) micrographs show that the lattice structures made by SLM have a good geometric agreement with the original computer-aided design (CAD) models, but many partially melted metal particles are bonded to strut surfaces. The struts within the gyroid cellular lattice structures with smaller unit cell sizes have higher densities due to their shorter scan vector lengths in the SLM process. The yield strength and Young''s modulus of the Gyroid cellular lattice structures increase with the decrease in the unit cell size due to the denser struts of the lattice structures with smaller unit cell sizes. [Copyright &y& Elsevier]

A D–A type organic luminogen single crystal (CIE-C) and its two Zn(ii) complexes [Zn(CIE-P)(C4H4N2)·CH3OH] (1) and [Zn(CIE-P)(4,4′-bipy)·1.5CH3OH] (2) (CIE-P = 2,3-bis(2,4-dihydroxybenzylideneamino)maleonitrile, C4H4N2 = pyrazine, 4,4′-bipy = 4,4′-bipyridine) have been synthesised and studied. The single crystal X-ray diffraction analysis showed that the molecular structure of CIE-C is well planar and the good co-planarity is maintained in the 2D structure; 1 and 2 are all mononuclear complexes. The photoluminescence properties of CIE-C and its Zn(ii) complexes have been investigated in the solid state and solution. The novel crystallization-induced emission-enhancement (CIEE) behavior of CIE-C and unusual fluorescence selectivity for THF of 1 and 2 were found. [ABSTRACT FROM AUTHOR]

To improve the sluggish kinetics of oxygen reduction reaction (ORR) is critically important for the development of fuel cells. It is generally recognized that catalysts with multi-transfer channels and varied active sites can energetically facilitate the ORR-relevant species transfer to improve the oxygen reduction rate. In this study, N-doped carbon nanotubes-crossed MoS 2 /carbon (N-MoS 2 /CNTs/C) catalysts are synthesized at temperatures of 600–900 °C using an in-situ reduction self-assembly method. In both acid (0.5 M H 2 SO 4 ) and alkaline (0.1 M KOH) media, N-MoS 2 /CNTs/C (800 °C) catalyst exhibits a promising ORR activity and favors a four-electron reduction pathway. The highly-maintained tubular CNTs in N-MoS 2 /CNTs/C (800 °C) can supply the multidimensional pathways for transferring the ORR-relevant species. N atoms doping can not only increase the structural defects of MoS 2 lattice (Mo–N x ) to expose more Mo–S x sites, but also induce various N functional groups into the carbon matrix (CNTs and porous carbon), which are favorable to improve the activation, adsorption and reduction of oxygen. Therefore, the distinct structures endow the N-MoS 2 /CNTs/C catalysts with high activity towards ORR. Furthermore, the N-MoS 2 /CNTs/C (800 °C) also exhibits a promising ORR activity in neutral medium (microbial fuel cells (MFCs)). MFCs with the N-MoS 2 /CNTs/C (800 °C) cathode exhibits the maximum power density of 987.4 mW m −2 , which is much higher than that of commercial Pt/C (601.96 mW m −2 ). These results indicate that N-MoS 2 /CNTs/C catalysts can be considered as a promising alternative to Pt/C for ORR. [ABSTRACT FROM AUTHOR]

C102H108Cl4Gd4N8O22, triclinic, P1̅ (no. 2), a = 11.4271(18) Å, b = 12.779(2) Å, c = 20.102(3) Å, α = 76.6197(17)°, β = 86.9059(18)°, γ = 71.4460(18)°, V = 2706.7(8) Å3, Z = 1, Rgt(F) = 0.0350, wRref(F2) = 0.1350, T = 296(2) K. [ABSTRACT FROM AUTHOR]

Four D–A type Zn(II) coordination complexes, [Zn(C29H29N3O2)·(CH3OH)]·(CH3OH) (1), Zn2(C74H90N6O4)·(CH3OH) (2), [Zn(C30H28N4O2)·(CH3OH)]·(CH3OH) (3) and [Zn(C38H44N4O2)·(C2H5OH)]·(C2H5OH) (4), were designed, synthesized, and studied. Their fluorescence properties in the solid state and in THF solution were comprehensively analysed based on their single-crystal structures. The results showed that the red-shift of fluorescence emission from complexes 1 to 4 was successfully achieved via the strategy of enhancing intramolecular charge transfer (ICT) effects by increasing the number of electron-pulling and pushing groups gradually. Meanwhile, because of the fluorescence recognition abilities of these four complexes towards iodide anions in THF, they could be regarded as potential fluorescent sensors for I− in this organic solution in the future. [ABSTRACT FROM AUTHOR]

The base-pair sequences are the foundation for the biological processes of DNA or RNA, and base-pair mismatch is very important to reveal genetic diseases and DNA rearrangements. However, the lack of well-defined structural information about base-pair mismatch is obstructing the investigation of this issue. The challenge is to crystallize the materials containing the base-pair mismatch. Engineering the small-molecule mimics or model is an effective strategy to solve this issue. Here, six cytidine-5′-monophosphate (CMP) and 2′-deoxycytidine-5′-monophosphate (dCMP) coordination polymers were reported containing cytosine-cytosine base-pair mismatch (i-motif), and their single-crystal structures and chiralities were studied. The precise control over the formation of the i-motif was demonstrated, in which the regulating of supramolecular interactions was achieved based on molecular design. In addition, the chiralities of these coordination polymers were investigated according to their crystal structures and solution- and solid-state circular dichroism spectroscopy. [ABSTRACT FROM AUTHOR]

Titanium (Ti) coatings on alumina (Al 2 O 3 ) balls fabricated by mechanical coating technique (MCT) were oxidized in air at a series of relatively low temperatures with the oxidation time of 3 h and 50 h. Crystal structure and microstructure of the coatings were investigated. Photocatalytic activity of the coatings was evaluated and discussed. The results showed that titanium dioxide (TiO 2 ) films on Ti or Ti/TiO 2 coatings were fabricated by the MCT and subsequent heat oxidation. The oxidized coatings started to show the mixed-phase of anatase and rutile, at the temperature of 873 K for 3 h and 773 K for 50 h. With extending the oxidation time from 3 h to 50 h, the oxidative effect of relatively lower temperatures of 773 K to 973 K almost reached to that of higher temperatures, which is similar to the time–temperature equivalence principle. Photocatalytic activity of anatase TiO 2 at 673 K is higher than that of mixed-phase or rutile TiO 2 under UV irradiation. [ABSTRACT FROM AUTHOR]