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We design and investigate a W 15 Ta 15 Cr 35 V 35 (at.%) multicomponent alloy (MCA) with exceptional radiation resistance. The sintered WTaCrV alloy exhibits a body-centered cubic (BCC) matrix with dispersed coherent ordered nanoprecipitates. After ∼3-hour irradiation under 400 keV He+ at room temperature (RT) and 450 °C with a fluence of 2 × 1017 ions/cm2, the irradiation hardening values of the MCA are about a quarter of those of pure tungsten counterparts irradiated at identical conditions. Besides, helium bubbles generated in the irradiated matrix of the MCA are much smaller, compared with those in the pure tungsten and other tungsten-rich alloys previously reported. The exceptional radiation resistance of the present WTaCrV alloy can be mainly attributed to two synergistic mechanisms. First, the high lattice distortion of the solid solution matrix promotes the local non-directional diffusion of irradiation defects, effectively suppressing the aggregation of irradiation defects and helium atoms along specific orientations. This facilitates more uniform nucleation of helium bubbles in the alloy matrix. Second, carbon was introduced during fast hot pressing sintering as interstitial solute to form carbon-rich coherent ordered nanoprecipitates. The carbon-vacancy complexes generated in the nanoprecipitates inhibit the nucleation and aggregation of helium atoms at the vacancies during He+ irradiation. The above two mechanisms synergistically enhance the resistance against He+ irradiation. This work thus demonstrates a design strategy for high radiation resistance alloys by introducing well-tuned ordered coherent nanoprecipitates in multicomponent alloy systems. [Display omitted] [ABSTRACT FROM AUTHOR]

Given that hydrogen production often involves impurities such as CO 2 , CH 4 , H 2 O, and alkanes, hydrogen purification is crucial for global green energy applications. Mixed matrix membranes (MMMs) using metal-organic framework (MOF) materials offer a non-thermal, energy-efficient method for hydrogen purification. These membranes have controllable structures and promote environmental sustainability. However, challenges such as filler aggregation and matrix-filler incompatibility during the preparation of MOF-MMMs are difficult to avoid and can adversely affect separation performance. In this study, 4-(trifluoromethyl) benzoic acid (4-TFMBA) was introduced in situ to grow synchronously with polyvinyl pyrrolidone (PVP) on UiO-66-NH 2 , forming a hydrophobic bifunctional nanoparticle composite, PVP-Zr-MOF-F. Furthermore, in situ loading of PVP-Zr-MOF-F onto a PVDF polymer matrix was achieved using a wet method and the NIPS technique to prepare PVP-Zr-MOF-F@PVDF. The introduction of 4-TFMBA, with highly electronegative F atoms, enhances hydrophobicity and increases H 2 affinity through polarization and hydrogen bonding induced by C–F bonds. PVP promotes the formation of smaller Zr-MOF particles, increases the proportion of small pores, prevents aggregation, and acts as a pore-forming agent, facilitating the in situ loading and dispersion of PVP-Zr-MOF-F within PVDF chains. This bifunctionalization not only improves the compatibility and dispersion of the nanofillers but also increases the number of small pores, enhancing van der Waals forces and confinement effects on H 2 molecules, making it suitable for gas separation under humid conditions. The results indicate that the H 2 permeance of PVP2–Zr-MOF-F@PVDF can reach 114,735 GPU, with selectivities of 19, 21, 24, and 120 for H 2 /CO 2 , H 2 /CH 4 , H 2 /C 2 H 4 , and H 2 / n -C 6 H 14 , respectively, surpassing the 2008 Robeson's upper bound. Notably, under high humidity conditions, the selectivities for H 2 /CO 2 , H 2 /CH 4 , and H 2 / n -C 6 H 14 are 1566 %, 1891 %, and 3264 % higher than those of the original PVDF membrane, achieving high selectivity separation. Additionally, after repetitive experiments with varying humidity, the membrane's selectivity remained almost unchanged, demonstrating the high hydrothermal stability of PVP2–Zr-MOF-F@PVDF. This research provides a new reference for hydrogen purification and holds significant implications for the sustainable development of green energy. [Display omitted] • Two-step in situ method for bifunctional hydrophobic MOF-MMMs. • PVP induces nucleation, prevents aggregation, and acts as a pore-forming agent. • Fluorine atoms enhance hydrophobicity and improve H 2 and hydrocarbon affinity. • High selectivity and permeability, enabling effective hydrogen purification. • Maintains efficient H 2 purification and hydrothermal stability under high humidity. [ABSTRACT FROM AUTHOR]