Due to their large specific surface area and abundant active surficial sites, MXenes can adsorb various environmental pollutants.

Plasma-facing materials and components in a fusion reactor are the interface between the plasma and the material part. The operational conditions in this environment are probably the most challenging parameters for any material: high power loads and large particle and neutron fluxes are simultaneously impinging at their surfaces. To realize fusion in a tokamak or stellarator reactor, given the proven geometries and technological solutions, requires an improvement of the thermo-mechanical capabilities of currently available materials. In its first part this article describes the requirements and needs for new, advanced materials for the plasma-facing components. Starting points are capabilities and limitations of tungsten-based alloys and structurally stabilized materials. Furthermore, material requirements from the fusion-specific loading scenarios of a divertor in a water-cooled configuration are described, defining directions for the material development. Finally, safety requirements for a fusion reactor with its specific accident scenarios and their potential environmental impact lead to the definition of inherently passive materials, avoiding release of radioactive material through intrinsic material properties. The second part of this article demonstrates current material development lines answering the fusion-specific requirements for high heat flux materials. New composite materials, in particular fiber-reinforced and laminated structures, as well as mechanically alloyed tungsten materials, allow the extension of the thermo-mechanical operation space towards regions of extreme steady-state and transient loads. Self-passivating

Electro-optical switching with low voltage, free hysteresis and fast response speed is achieved in a facile manner by dispersing a small amount of ferroelectric nanoparticles (NPs) into blue phase liquid crystal. The large dipole moment of NPs contributes to the hysteresis-free switching, whereas the low voltage operation results from the introduction of the ferroelectric properties inherent to the NPs.Blue phase (BP) liquid crystal display (LCD) devices based on the optical Kerr effect are emerging as some of the leading candidates for the next-generation display technology because they exhibit the following revolutionary features: 1 (1) submillisecond gray-to-gray response time that enables field sequential display without using color filters, (2) no need for a surface alignment layer which greatly simplifies the fabrication process, (3) wide and symmetric viewing angle, and (4) cell-gap insensitivity provided that an in-planeswitching (IPS) electrode is employed. Recent developments that introduce BPs with an extended temperature range 2 make them more attractive for applications in LCDs, and Samsung Co. demonstrated the first BP LCD prototype based on polymer stabilized BPs (PSBP) in 2008. 3 However, some bottlenecks such as voltage-induced serious hysteresis and high driving voltage, still remain to be overcome before widespread applications of BP LCD can take off. The hysteresis-free BPLC has been previously achieved by introducing the polymers with flexible chains or the inorganic NPs with large dipole moment, 2d,4 but the high driving voltage (>50.0 V) is a big challenge on the road toward practical applications. Therefore, there is an urgent need to explore a novel strategy to reduce the driving voltage and develop the BP composites with low driving voltage and free hysteresis.It has already been theoretically predicted that the driving voltage (on-state voltage, V on ) is closely related to the Kerr constant of materials and the electrode configuration of devices, and a large Kerr constant or a uniform electric field which penetrates deeply into the bulk liquid crystal (LC) layer helps to reduce the driving voltage of BP LCD. 5 Extensive work on developing new BPLC materials and low-voltage device structures has been recently performed. On the one hand, to enlarge the Kerr constant, the materials with large intrinsic birefringence and dielectric anisotropy have been prepared by the conventional time-consuming and expensive chemically synthetic methods, 6 whereas enhancing the Kerr constant by increasing the Dn$D3 of host LCs unavoidably leads to increased viscosity, which in turn lengthens the response time. On the other hand, to optimize the device structures, several new electrode configurations, such as protrusion electrode, 7 wall-shaped electrode, 8 corrugated electrode 9 and vertical field switching (VFS) electrode, 10 have been proposed one after the other. Despite their remarkable achievements in reducing the driving voltage, many other problems such as sophisticated device fabrication, noticeab...

Oxide dispersion strengthened (ODS) steels exhibit exceptional radiation resistance and hightemperature creep strength when compared to traditional ferritic and ferritic/martensitic (F/M) steels. Their excellent mechanical properties result from very fine nanoparticles dispersed within the matrix. In this work, we applied a high-energy synchrotron radiation X-ray to study the deformation process of a 9Cr ODS steel. The load partitioning between the ferrite/martensite and the nanoparticles was observed during sample yielding. During plastic deformation, the nanoparticles experienced a dramatic loading process, and the internal stress on the nanoparticles increased to a maximum value of 3.5 GPa, which was much higher than the maximum applied stress (~986 MPa). After necking, the loading capacity of the nanoparticles was significantly decreased due to a debonding of the particles from the matrix, as indicated by a decline in lattice strain/internal stress. Due to the load partitioning, the ferrite/martensite slightly relaxed during early yielding, and slowly strained until failure. This study develops a better understanding of loading behavior for various phases in the ODS F/M steel.

In the present work, reduced-activation ferritic/martensitic (RAFM) steels including

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α–Si3N4 whiskers were fabricated first through combustion synthesis (CS) technology. The as-synthesized crystals with [001] as the elongated axis contain a large amount of linear defects including (a + b)-type, (a + b + c)-type, and c-type of dislocations. The growth of α–Si3N4 whiskers is mainly controlled by vapor-condensation (VC) mechanism. Special additive plays an important role in promoting the growth of α–Si3N4 whiskers and suppressing the phase transformation of α–Si3N4 to β–Si3N4.

a b s t r a c tAn oxide dispersion-strengthened (ODS) 316 steel was developed to simultaneously provide the advantages of ODS steels in mechanical strength and radiation tolerance as well as the excellence of austenitic steels in creep performance and corrosion resistance. The precipitate phases within the austenite matrix were identified by the combined techniques of atom probe tomography (APT), scanning transmission electron microscopy equipped with electron dispersive X-ray spectroscopy (STEM-EDS), and synchrotron wide-angle and small-angle X-ray scattering (WAXS and SAXS). Coarse TiN, hexagonal YAlO 3 and orthorhombic YAlO 3 precipitates were found along with fine Y-Ti-O nanoparticles. In situ WAXS experiments were performed at room and elevated temperatures to examine the size effect on the load partitioning phenomenon for TiN, hexagonal YAlO 3 and Y 2 Ti 2 O 7 phases. In addition, the dislocation density evolution throughout the tensile tests was analyzed by the modified Williamson-Hall method and confirmed by transmission electron microscopy (TEM) observations, revealing the difference in plasticity at various temperatures.