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This study investigates the damping properties of Cu–Al–Mn shape memory alloys (SMAs) with various chemical compositions and the effects of the addition of quaternary alloying elements Ag and Nb on the microstructure, martensitic transformation behavior, and damping capacity of SMAs. Compared to other Cu–12Al– x Mn (x = 4–7 wt%) SMAs, Cu–12Al–5Mn has a more significant inherent and intrinsic internal friction (IF PT + IF I) peak above room temperature. The addition of Ag or Nb to Cu–12Al–5Mn reduced the grain size, thereby increasing the hardness of the alloys; however, the damping capacity and temperature of the IF PT + IF I peak decreased simultaneously. The addition of Ag to Cu–12Al–5Mn significantly reduced the damping capacity (IF PT +IF I peak) because of the notable decrease in the amount of transformed martensite. Moreover, the addition of Nb to Cu–12Al–5Mn caused the AlNb 3 phase to precipitate, limiting the mobility of the martensite variant interfaces and slightly decreasing the damping capacity (IF PT + IF I peak). Among the Ag- and Nb-doped Cu–12Al–5Mn SMAs, Cu–12Al–5Mn–1 Nb showed not only a significantly higher hardness but also a higher IF PT + IF I peak, with tan δ exceeding 0.01 at approximately 50 °C. [Display omitted] • In Cu-based SMAs, damping capacity depends on microstructure and the volume fraction of the transformed martensite. • Alloying elements with different mechanisms affect the damping performance of Cu-based SMAs. • In Cu-based SMAs, both damping capacity and mechanical strength improve by optimizing chemical composition. [ABSTRACT FROM AUTHOR]

The construction of multidimensional composite photocatalysts with substantial photocatalytic performance, fast charge separation, and a wide light absorption range system poses a major challenge to the field of photocatalytic research. Here, ZnO nanorods with assembling ZnIn 2 S 4 nanosheets via a hydrothermal approach to construct a unique Z-scheme 2D/1D ZnIn 2 S 4 /ZnO heterojunction photocatalyst. The morphology, composition, microstructure, and properties of the 2D/1D ZnIn 2 S 4 /ZnO photocatalyst were thoroughly investigated through a variety of detailed characterizations. Scanning electron microscopy (SEM) and transmission electron microscope (TEM) findings showed that a significant number of ZnIn 2 S 4 nanosheets evenly grew on the surface of ZnO nanorods. Based on the XPS investigation, the close chemical interaction between ZnIn 2 S 4 and ZnO was identified. The visible light absorption range of the as-prepared photocatalysts was expanded, facilitating electron–hole separation upon photoexcitation according to UV–vis DRS and electrochemical tests. Under light radiation, the 2D/1D ZnIn 2 S 4 /ZnO photocatalyst can degrade 96.84 % of methyl orange (MO) within 120 min. Furthermore, the photocatalytic hydrogen evolution rate reached 3348.3 μmol/g/h within 6 h. The enhanced photocatalytic performance was substantial because of the Z-scheme system formed between ZnIn 2 S 4 and ZnO and the 2D/1D nanostructures' nature, which facilitated carrier transfer and increased the number of active sites for photocatalytic reactions. The charge transfer mechanism of ZnIn 2 S 4 /ZnO was discussed in detail according to radical trapping experiments. We expect that the fabrication of 2D/1D materials with a Z-scheme system will offer new ideas and record the development of high-efficiency energy conversion photocatalysts. [Display omitted] • 2D/1D ZnIn 2 S 4 nanosheets/ZnO nanorods hetrojunction have been successfully synthesized. • ZnIn 2 S 4 /ZnO photocatalysts improved hydrogen production and dye degradation activity. • The 2D/1D heterojunction and Z-scheme system play effective role in the photocatalysis. • The mechanism of separation and migration of charge carriers was proposed. [ABSTRACT FROM AUTHOR]

• K 2 SiF 6 :Mn,Na@GQDs@K 2 SiF 6 were synthesized. • Sample exhibits a good water resistance induced by coating of K 2 SiF 6. • Samples with negative thermal quenching can be easily obtained by double coating. • The negative thermal quenching is caused by energy conversion from heat into light. Nowadays, it is still a big challenge to synthesize Mn4+-doped fluoride red phosphors with high water resistance, luminescent intensity and thermal stability simultaneously. Therefore, KSF:M,N@GQDs@KSF (K 2 SiF 6 :0.06Mn,0.10Na@GQDs (12 mg/mol) @K 2 SiF 6 (0.2 wt) , KSF: K 2 SiF 6 , GQDS: OH-contained graphene quantum dots) with high luminescent intensity, high luminescent thermal stability and water resistance have been synthesized via a combination of H 2 O 2 -free room temperature reaction method, hydrothermal coating method and room temperature surface coating process. Experimental results show that enhancement of negative thermal quenching (NTQ) effect and water resistance can be synergistically induced by double coating of GQDs and KSF. After being immersed in deionized water for 360 min, emission intensities of the KSF:M,N@GQDs and KSF:M,N@GQDs@KSF are decreased from 100% to 70.57% and 91.63%, respectively, indicating that water resistance of the latter is obviously improved by coating of KSF. The improved water resistance is attributed to preventing hydrolysis of [MnF 6 ]2- on sample's surface by insoluble coating shell of KSF. A prototype WLEDs (white light-emitting diodes) emitted warm white light (CCT = 4546 K and Ra = 91.3, at a driving current of 20 mA) has been assembled by coating mixture of KSF:M,N@GQDs@KSF, yellow emitting phosphor (YAG:Ce3+) and epoxy resin on blue light InGaN chips. The good performances of the WLEDs suggest that the KSF:M,N@GQDs@KSF has potential applications in blue-based warm WLEDs. [ABSTRACT FROM AUTHOR]

Abstract: The phase equilibria in the Co–W–V ternary system were experimentally investigated by optical microscopy (OM), electron probe microanalysis (EPMA) and X-ray diffraction (XRD) on the equilibrated alloys. Three isothermal sections of the Co–W–V ternary system at 1100°C, 1200°C and 1300°C were determined, and no ternary compound was found in this system. In addition, a novel phenomena induced by the liquid phase separation in the Co–W–V alloys was firstly discovered, suggesting that a stable liquid miscibility gap exists in the Co–W–V ternary system. The newly determined phase equilibria and firstly discovered phase separation phenomena in the Co–W–V system will provide important information for the development of Co–W based alloys. [Copyright &y& Elsevier]

Modulating the morphology of metal-organic frameworks (MOFs) has been identified as an effective strategy for enhancing the electrocatalytic performance of CO 2 reduction reactions (CO 2 RR). In this study, CAU-17 MOFs ([Bi(BTC)(H 2 O)]·2 H 2 O·MeOH) were prepared via a sonication-assisted method at room temperature, which is considered a simpler technique compared to the conventional hydrothermal method. Additionally, the morphology of CAU-17 MOFs was further regulated by incorporating a rare-earth metal (La), resulting in the observation of two distinct structures, i.e. CAU-17 hexagonal prism (CAU-17-HP) and CAU-17 layer (CAU-17-Layer). Compared to CAU-17-HP, CAU-17-Layer exhibits an excellent selectivity towards formate with the maximum Faradaic efficiency of 95.5% at − 1.1 V RHE in an H-cell. Subsequently, the limited catalytic activity of CAU-17-Layer was boosted by anchoring nano CeO 2 onto its surfaces (CeO 2 @CAU-17-Layer). The as-prepared composite catalyst demonstrated outstanding performance in the conversion of CO 2 to formate, with a current density surpassing − 100 mA cm-2 at potentials more negative than − 1.0 V RHE and reaching − 200 mA cm-2 at − 1.5 V RHE in a flow cell. This study demonstrates the significant potential of morphology-engineered and rare-earth metals composited MOFs in facilitating highly efficient reduction of CO 2. • Bismuth-based metal-organic frameworks (CAU-17 MOFs) were prepared via a sonication-assisted method at room temperature. • The morphology of CAU-17 MOFs was regulated by rare-earth metal (La). • Morphology engineering boosted the catalytic performance of CAU-17-MOFs. • When incorporating nano-CeO 2 into CAU-17-Layer, the current density reached − 200 mA cm-2 at − 1.5 V RHE. [ABSTRACT FROM AUTHOR]

In this paper, bayberry-like BiOBr/AgBr/LaPO 4 nanocomposites were synthesized by microwave-assisted hydrothermal treatment. The composition, structure, and morphology of BiOBr/AgBr/LaPO 4 nanocomposites were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV−visible diffuse reflectance (UV−vis/DRS), high-power transmission electron microscopy (HR-TEM), scanning electron microscopy (SEM), and N 2 adsorption−desorption measurements. The results show that the light absorption capacity of BiOBr/AgBr/LaPO 4 is clearly enhanced and that a bayberry-like structure is more likely to produce diffraction and reflection of light on the surfaces of composites. AgBr in the composite is capable of reducing to Ag0 after light irradiation. Ag0, acting as a charge-transfer mediator, can be the medium, thus forming a Z-scheme structure. At the same time, the surface plasmon resonance (SPR) effect of Ag0 exhibits higher activity in the simulated sunlight photocatalysis process in BiOBr/AgBr/LaPO 4. The photoelectrochemical methods further indicate that BiOBr/AgBr/LaPO 4 possesses the best electron−hole pair separation ability. Furthermore, two different interface electron transfer modes and multipathway photoelectron migration in the composite are determined. • A bayberry-like structure BiOBr/AgBr/LaPO 4 composite was synthesized. • AgBr in the composite is capable of reduction to form Ag0 after light irradiation. • The presence of Ag0 results in forming two different electron transport pathes. • Two electron transfer modes synergistically improve photocatalytic ability. [ABSTRACT FROM AUTHOR]

The critical behavior and magnetocaloric properties with a room-temperature second-order phase transition of the Mn 5 Ge 3- x Ag x (x = 0, 0.1, 0.5, and 1) compounds under the increasing field and decreasing field were studied in detail. The Curie temperature shifts from 299.8 K to 291.5 K with increasing Ag doping content, and the second-order nature has been proved by several tools. Moreover, x = 0 gives the maximum magnetic entropy change near the room temperature, and the corresponding values for both the demagnetization and the magnetization are 7.25 J/kg K and 7.31 J/kg K with a negligible hysteretic loss of 0.447 J/kg at an applied field change of 5 T. The critical exponents have been estimated by various techniques to clarify the magnetic exchange interaction, which is not accordant with a single universality class, and the range of interaction reveals a 3D Ising spin interactions in this series. These results suggest that the present system seems an effective magnetic refrigerant for application in room-temperature magnetic refrigeration. [Display omitted] • The magnetic transition was confirmed by different techniques. • The hysteretic losses from the enclosed area between M (H) were determined. • Critical behavior under the increasing and decreasing fields were studied. • The exchange distance was performed to clarify the interaction couplings. [ABSTRACT FROM AUTHOR]

Mn4+-activated fluoride is a kind of high-efficiency red-emitting phosphor widely used in WLEDs (white light-emitting diodes). However, the poor moisture resistance hampers their commercial application on a large scale. Here, a new type of organic-inorganic hybrid KSF:HMTA, Mn4+ (KSF:K 2 SiF 6 , HMTA: hexamethylenetetramine) red-emitting phosphor has been prepared through the cation exchange method. Compared with KSF:0.04Mn4+, emission intensity, florescent thermal stability, and water resistance of KSF:HMTA,0.04Mn4+ are improved significantly due to the formation of MOF (metal-organic framework) between HMTA and K 2 MnF 6. MOF creates an antenna effect and forms an insoluble protective shell on the sample surface. The former induces the negative thermal quenching (NTQ) effect via phonon-excited electron interaction, significantly improving the florescent thermal stability. The latter prevents the contact of Mn4+ ions on the sample surface with water molecules, resulting in enhancement of waterproofness. The formation mechanism of the MOF was discussed. A prototype WLED with warm white light (CCT = 3815 K and Ra = 90.4) were assembled via coating a mixture of YAG:Ce3+, KSF:HMTA,0.04Mn4+ and epoxy resin on a blue-emitting chip (450 nm). The results show that KSF:HMTA, 0.04Mn4+ is a potential red-emitting phosphor that can be used on its part of WLEDs. [Display omitted] • KSF:HMTA, Mn4+ has been synthesized. • Sample has high water resistance, thermal stability and luminescent intensity. • Water resistance, thermal stability and emission intensity are enhanced by formation of MOF. • The negative thermal quenching is attributed to the increase of suitable electron traps. [ABSTRACT FROM AUTHOR]

The influence of Gd element and solution treatment on the microstructure of AZ31 alloy was investigated in this paper. The microstructure and phase composition were characterized by OM, SEM, EDS and XRD. The results indicate that Mg 17 Al 12 eutectic phase, scattered along the grain boundary, is suppressed effectively with Gd addition and the acicular Al 2 Gd superlattice with lamellar distribution is formed. Furthermore, the grain size of AZ31 alloy is also refined with Gd addition. In the subsequent process of solution, the migration and growth of Al 2 Gd phase conforms to Ostwald Ripening Theory. The morphology of Al 2 Gd phase becomes granular and scatterd in matrix uniformly after solution for 16 h at 813 K. [ABSTRACT FROM AUTHOR]

Fe-doped SrMoO 4 (SrMo 0.94 Fe 0.06 O 4−δ ), synthesized by an EDTA–glycine complexing combustion process, can be easily reduced to SrMo 0.94 Fe 0.06 O 3−δ (SMF) at 850 °C in pure H 2 atmosphere. The incorporation of Gd 0.2 Ce 0.8 O 1.9 (GDC) into SrMo 0.94 Fe 0.06 O 3−δ is supposed to enhance the ionic conductivity and catalytic activity of SMF. Phase composition and chemical compatibility of SMF-GDC composite in both air and H 2 atmosphere are confirmed by X-ray diffraction test. SMF-GDC composites in different mass ratios are systematically investigated in terms of electrical conductivity, electrochemical performance and power output with the fuel cells. With the addition of GDC, the ionic conductivity is able to be improved and the lowest interfacial polarization resistance is observed to be 0.647 Ω cm 2 for SMF7-GDC3 composite anode at 850 °C. With SMF7-GDC3 as anode, the single cell is able to generate a maximum power density of 530 mW cm −2 at 850 °C when fed with pure H 2 (30 mL min −1 ) and demonstrates a considerable stability with the anode exposed to H 2 and upon redox cycling. [ABSTRACT FROM AUTHOR]

• A ball-milling method was used to produce the uniform mixing of Mn-BTC and rGO. • The rGO/Mn 3 O 4 composite was fabricated via the annealing of Mn-BTC with rGO. • The bead-string-like Mn 3 O 4 on rGO attains superior capacitance and cycle life. • The assembled symmetric supercapacitor exhibits good electrochemical performance. [Display omitted] Metal oxide derived from metal-organic framework (MOF) could possess unique architecture and special properties. In this work, hierarchically nanostructured Mn 3 O 4 is synthesized from the thermal annealing of manganese-1,3,5-benzenetricarboxylate (Mn-BTC) MOF with the presence of reduced graphene oxide (rGO) to yield rGO/Mn 3 O 4 composite for the high-performance supercapacitor electrode material. The porous rGO aerogel is prepared from the hydrothermal and freeze-drying processes. The effective combination of Mn-BTC and rGO aerogel is realized through a facile ball-milling method that endows Mn-BTC with a rod-like structure in the composite. Upon annealing, the Mn-BTC-derived Mn 3 O 4 presents the unique structure of porous rods comprising nanoparticles in the resulting rGO/Mn 3 O 4 composite. The optimized rGO/Mn 3 O 4 /Ni foam electrode achieves a specific capacitance of 420 F g−1 at 0.5 A g−1 and a superior cycling property. The assembled all-solid-state symmetric supercapacitor based on rGO/Mn 3 O 4 composite delivers the energy density of 22.1 Wh kg−1 and power density of 3.0 kW kg−1. The excellent capacitive performance of the rGO/Mn 3 O 4 electrode could be ascribed to the effective integration of Mn-BTC-derived manganese oxides with hierarchical structure and the rGO matrix, facilitating the ion/electron transport in the electrochemical process. [ABSTRACT FROM AUTHOR]

• CdS QDs 3DOH ZnTiO 3 -ZnO-TiO 2 composite was prepared by PS microspheres as the template. • The composite modified by CdS QDs has a good light absorption range. • Three-dimensional ordered hollow spherical structure enhances the charge transfer. • As-hollow structure offers more suitable transport channels for reactive molecules. • A rate of hydrogen evolution of CdS QDs 3DOH ZnTiO 3 -ZnO-TiO 2 is 300 times of TiO 2. Three-dimensional ordered hollow spherical ZnTiO 3 -ZnO-TiO 2 composite (3DOH ZnTiO 3 -ZnO-TiO 2) was prepared by vacuum impregnation combined with calcination method using polystyrene (PS) colloidal microspheres as the template, and the CdS QDs were modified into 3DOH ZnTiO 3 -ZnO-TiO 2 by water bath method. The crystal structure, chemical composition, surface morphology, optical absorption and surface physicochemical properties of CdS QDs modified 3DOH ZnTiO 3 -ZnO-TiO 2 (CdS QDs 3DOH ZnTiO 3 -ZnO-TiO 2) composite were well characterized. The results show that the three-dimensional ordered hollow spherical CdS QDs 3DOH ZnTiO 3 -ZnO-TiO 2 composite mainly composes of anatase phase TiO 2 , rutile phase TiO 2 , and hexagonal phase ZnTiO 3 and hexagonal phase ZnO. Among them, a homojunction is formed between the mixed crystal phase of TiO 2 (anatase–rutile), and a heterojunction is found between hexagonal phase ZnTiO 3 and hexagonal phase ZnO. In addition, the composite treated by the polystyrene (PS) colloidal microspheres template has formed the three-dimensional ordered hollow sphere structure, the hollow spheres are arranged neatly and orderly, and the sphere wall is formed by stacking nanoparticles. At the same time, the three-dimensional ordered hollow spherical structure of CdS QDs 3DOH ZnTiO 3 -ZnO-TiO 2 composite provides more transfer paths for material transport and promotes repeated light absorption, prolonging the lifetime of photogenerated charge carriers. Moreover, due to the close connection between CdS QDs, ZnTiO 3 , ZnO and TiO 2 , the separation of electrons and hole pairs is facilitated, and the recombination of electron and hole pairs is effectively suppressed, so that CdS QDs 3DOH ZnTiO 3 -ZnO-TiO 2 composite exhibits extremely high photocatalytic activity. Its hydrogen production is more than 300 times that of pure TiO 2 , moreover, of which cycle stability also shows better. [ABSTRACT FROM AUTHOR]

In this work, CdS@ZnS–ZnO composites were prepared by the temperature-programmed hydrothermal method combined with the microwave-assisted hydrothermal method. The composite consisted mainly of cubic phase ZnS, hexagonal phase CdS and hexagonal phase ZnO, and presented a spherical structure with relatively uniform size and shape. There were heterostructures between CdS, ZnS and ZnO in the spherical structure. At the same time, the grain size, specific surface area, average pore diameter and pore volume of the composited material changed significantly, and its light absorption performance in the visible light region was obviously enhanced, and the photocatalytic activity was also greatly improved. Under ultraviolet light, CdS@ZnS–ZnO can degrade simulated pollutants by more than 90% within 20 min. In addition, the results of hydrogen evolution from photolysis of water showed that the ternary composite CdS@ZnS–ZnO had excellent hydrogen evolution capacity compared with pure CdS, ZnS and ZnO, whose hydrogen evolution amount can reach 3647 μmol g−1 in 8 h, was 298 times than that of P25. Moreover, it still maintained a high hydrogen evolution capacity after 4 cycles. Image 1 • Established spherical structure ternary photocatalyst CdS@ZnS–ZnO. • Discussing type II heterojunction and the Z-scheme charge transfer process in CdS@ZnS–ZnO. • Within 20 min, simulated pollutants can be degraded more than 90%. • The hydrogen evolution amount of CdS@ZnS–ZnO can reach 3647 μmol g−1. [ABSTRACT FROM AUTHOR]