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On account of the relatively high theoretical capacity and lamellar structure, MoSe 2 is considered as an advanced anode material applied for sodium-ion batteries (SIBs). Unfortunately, the notorious issues of MoSe 2 including low electrical conductivity, tendency to restack and aggregate and high mechanical stress during cycling usually lead to the rapid deterioration of sodium storage properties. Herein, we propose the rational design and fabrication of NiSe 2 nanoparticles decorated flower-like MoSe 2 nanosheets simultaneously confined in N-doped carbon spheres (denoted as MoSe 2 -NC/NiSe 2) via successive solvothermal and selenization steps. The heterostructure as generated between NiSe 2 and MoSe 2 can effectively provide more rich redox chemistry and synergistic merits. Meanwhile, the derived N-doped carbon matrix can protect the MoSe 2 nanosheets from agglomeration, facilitate the electron transport in the composite, and accommodate the volume variation with the help of unique porous structure. Accordingly, the hybrid composite of MoSe 2 -NC/NiSe 2 presents a high capacity of 315 mAh g−1 at 1 A g−1 and high-rate feature with 146 mAh g−1 even over 2000 cycles at 5 A g−1, demonstrating the excellent sodium storage performance including fast charging/discharging and outstanding cycling durability when applied in SIBs. • The N-doped carbon prevents agglomeration of nanosheets and enhances the electron transfer ability. • The heterostructure provides more electroactive sites and increased (100) interlayer spacing of MoSe 2. • The hybrid composite of MoSe 2 -NC/NiSe 2 anode shows durable cyclic stability and outstanding rate capability. [ABSTRACT FROM AUTHOR]

For SiC p /Al composites, the stability of the interface between SiC particles (SiC p ) and matrix is crucial. A novel method, in-situ coating of ex-situ SiC p , is developed in hypereutectic Al-Si alloys within this research. The microstructure, growth mechanism and strengthening behavior of the ex-situ SiC p with in-situ SiC coating were studied. Microstructure observation shows that due to the formation of in-situ coating, the interfacial bonding of ex-situ SiC p and matrix is improved. Further research reveals the epitaxial growth character of the in-situ SiC coating which has the same structure with ex-situ SiC p . The ex-situ SiC p with in-situ SiC coating is easily introduced into complex Al-Si alloys and the tensile strength of the alloy at both room temperature and 350 °C is improved remarkably. [ABSTRACT FROM AUTHOR]

Highlights: [•] Morphology evolution of ZrAlSi phase in Al–18Si–xZr alloys was detected. [•] The morphology transforms from flake-like to block-like with Zr content. [•] Effect of different morphological ZrAlSi on the properties of an A–Si piston alloy was studied. [•] Blocky ZrAlSi phase is good for the elevated-temperature tensile strength. [Copyright &y& Elsevier]

Developing high-strength Al-based alloys that can operate at 250 °C and above remains a challenge. In this study, a heat-resistant and high-strength (4TiC + 5AlN)/Al–Fe–Mn composite is designed using the liquid–solid reaction and hot extrusion. The strengthening phases, including sub-micron TiC, micron Al 3 (Fe, Mn), nano-sized AlN, and nano-sized Al 3 (Fe, Mn), in which the in–situ AlN particles are distributed in the matrix as networks, exhibit an attractive strengthening effect. Based on the results of electron backscatter diffraction, the extruded (4TiC + 5AlN)/Al–Fe–Mn composite prefers to form fiber texture in the longitudinal and cross-section:<111> Al //ED. And the average grain size of (4TiC + 5AlN)/Al–0.3Fe–0.1Mn composite is 0.69 µm. The ultimate tensile strength of the (4TiC + 5AlN)/Al–Fe–Mn composite is as high as 215 MPa at 350 °C. And the high-temperature elongation of the (4TiC + 5AlN)/Al–Fe–Mn composite is maintained while increasing the high-temperature strength. The improved performance of the (4TiC + 5AlN)/All–Fe–Mn is attributed to the synergistic effect of the multi-scale Al 3 (Fe, Mn) phases and particles. Furthermore, the formed micrometer Al 3 (Fe, Mn) phases are used to regulate the distribution of the TiC and AlN particles. The nano-Al 3 (Fe, Mn) dispersoids that precipitated during the homogenization can enhance the high-temperature deformation resistance of the matrix. In particular, the Fe and Mn atoms tend to aggregate at the TiC/Al interface, effectively modifying the interfaces between ex-situ TiC particles and the Al matrix. The modified interfaces of TiC/Al are beneficial to load transfer strengthening. The strengthening mechanisms of the (4TiC + 5AlN)/Al–Fe–Mn composite have been analyzed in detail, and the main strength–increasing mechanisms are calculated from the microstructural data. This work may provide an important approach to preparing heat-resistant Al matrix composites with strength-ductility matching. • The UTS of (4TiC + 5AlN)/Al–0.3Fe–0.1Mn composite at 350 °C can reach 215 MPa and maintain a certain degree of ductility. • The synergistic effect of particles and multi-scale Fe/Mn enrichment is responsible for the enhanced UTS of A 3 composite. • The main strengthening mechanisms of A 3 composite were calculated through the microstructural data. [ABSTRACT FROM AUTHOR]

Hard carbon with large interlayer spacing is suitable as the anode material for sodium-ion batteries. Rape seed shuck derived lamellar hard carbon is synthesized through hydrothermal and pyrolysis processes. As the anode, it exhibited good cycling stability, delivering a capacity of 143 mAh g −1 after 200 cycles at 100 mA g −1 . The promising performances are attributed to the sheet structure with expanded interlayer distance (0.39 nm) and much void which can lower the sodium-ion insertion-extraction barrier and promote Na-ion diffusion and storage. The effect of pyrolysis temperature on the performance is also investigated. [ABSTRACT FROM AUTHOR]

Accelerating the carrier transfer and increasing the effective reaction site on the surface of photocatalyst are important measures to improve the hydrogen production of composite photocatalyst. Herein, through simultaneous carbonization and phosphorization strategies, a Ni-based metal-organic frameworks (MOFs) derived method is presented to prepare a promising cost-effective Ni–P@C cocatalyst and couple with S-vacancy ZnIn 2 S 4 (Vs-ZIS) for boosting photocatalytic activity. In this system, abundant S vacancies are induced to the surface of ZnIn 2 S 4 ultrathin sheets (4 nm thickness) to capture photoinduced electrons, thus avoiding the recombination of carriers on the surface of ZnIn 2 S 4. Furthermore, Ni–P is introduced to enhance the transfer of photogenerated electrons and increase the reaction site, and the synthesized Ni–P@C cocatalyst is developed to act as electronic container where the carbon framework with graphitic sp2 hybridized structures enables strong electronic interactions at the interface layer. The Ni–P@C/Vs-ZIS-2 photocatalyst exhibits a robust H 2 evolution rate of 11,064 μmol g−1 h−1, higher than Vs-ZIS (1542 μmol g−1 h−1) and ZIS (398 μmol g−1 h−1), and the apparent quantum efficiency of Ni–P@C/Vs-ZIS-2 is 12.4%. This study uncovers the role of surface S-vacancy of the ultrathin two-dimensional catalyst ZnIn 2 S 4 coupling with Ni–P@C cocatalyst in affecting electron transfer and reaction site, opening new opportunities for achieving efficient hydrogen production. This work introduces the synthesis of Ni–P@C/Vs-ZIS sheet heterostructure photocatalysts and the application of photocatalytic hydrogen evolution. Image 1 • A n-type ZnIn 2 S 4 semiconductor with S vacancy is fabricated in pure DMF solution. • Ni-MOF serves as a template to prepare core-shell Ni–P@C cocatalyst. • Ni-MOF-derived Ni–P@C has metallic character, the enhanced photocatalytic effect from the transfer and consumption of electrons is significantly accelerated. • The Ni–P@C/ZIS-2 shows excellent activity and robust stability in photocatalytic reactions. [ABSTRACT FROM AUTHOR]

In this paper, a new kind of AlTiC–B master alloy, containing large amounts of nano‒sized TiC particles, has been applied in 7050 alloy. The influence of master alloy addition on the casting microstructures, extrusion behaviors and mechanical properties of 7050 has been investigated. It is found that 0.5 wt% addition of AlTiC–B master alloy exhibits the most attractive performance, resulting in much finer matrix grains and less casting defects. After hot extrusion, typical <100> and <111> fiber textures co‒exist in the microstructure of original 7050 alloy, whereas the alloys with AlTiC–B inoculation possess a higher intensity of <111> fiber texture. Besides, the inoculated alloys show better anti–recrystallization performance and larger local misorientation. It has been confirmed that a proper addition of AlTiC–B master alloy is beneficial for the mechanical properties of extruded 7050, which may be due to its refining effect on α–Al grains and its improvement for the precipitation of L1 2 –ZrAl 3. The Brinell hardness, ultimate tensile strength, yield strength and elongation of 7050 alloy with 0.5 wt% addition of AlTiC–B addition are 174 HBW, 665 MPa, 724 MPa and 9.8%, respectively. This work provides a promising prospect of AlTiC–B master alloy for applying in 7050 alloy in industries. • Research highlights: • A new AlTiC–B master alloy with B doped nano‒sized TiC particles was applied on 7050 alloy. • Improvement of casting quality and grain refining can be achieved with AlTiC–B inoculation. • Texture intensity and recrystallization fraction of as‒extruded 7050 vary with AlTiC–B addition. • Mechanical properties can be significantly improved. [ABSTRACT FROM AUTHOR]