Nanocrystalline (NC) metals are stronger and more radiation-tolerant than their coarse-grained (CG) counterparts, but they often suffer from poor thermal stability as nanograins coarsen significantly when heated to 0.3 to 0.5 of their melting temperature (Tm). Here, we report an NC austenitic stainless steel (NC-SS) containing 1 at% lanthanum with an average grain size of 45 nm and an ultrahigh yield strength of ~2.5 GPa that exhibits exceptional thermal stability up to 1000 °C (0.75 Tm). In-situ irradiation to 40 dpa at 450 °C and ex-situ irradiation to 108 dpa at 600 °C produce neither significant grain growth nor void swelling, in contrast to significant void swelling of CG-SS at similar doses. This thermal stability is due to segregation of elemental lanthanum and (La, O, Si)-rich nanoprecipitates at grain boundaries. Microstructure dependent cluster dynamics show grain boundary sinks effectively reduce steady-state vacancy concentrations to suppress void swelling upon irradiation.

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Single-crystal-like nanotwinned Nickel was prepared via a hybrid technique and it renders superb mechanical behaviors and corrosion resistance.

Despite the essential role of ethylene carbonate (EC) in solid electrolyte interphase (SEI) formation, the high Li+ desolvation barrier and melting point (36 °C) of EC impede lithium-ion battery operation at low temperatures and induce sluggish Li+ reaction kinetics. Here, we demonstrate an EC-free high salt concentration electrolyte (HSCE) composed of lithium bis­(fluorosulfonyl)­imide salt and tetrahydrofuran solvent with enhanced subzero temperature operation originating from unusually rapid low-temperature Li+ transport. Experimental and theoretical characterizations reveal the dominance of intra-aggregate ion transport in the HSCE that enables efficient low-temperature transport by increasing the exchange rate of solvating counterions relative to that of solvent molecules. This electrolyte also produces a <5 nm thick anion-derived LiF-rich SEI layer with excellent graphite electrode compatibility and electrochemical performance at subzero temperature in half-cells. Full cells based on LiNi0.6Co0.2Mn0.2O2||graphite with tailored HSCE electrolytes outperform state-of-the-art cells comprising conventional EC electrolytes during charge–discharge operation at an extreme temperature of −40 °C. These results demonstrate the opportunities for creating intrinsically robust low-temperature Li+ technology.

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Mo enriched thick GBs in nanocrystalline Ni alloy are stronger barriers than conventional GBs to the transmission of dislocations.

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The integration of highly luminescent CsPbBr3 quantum dots on nanowire waveguides has enormous potential applications in nanophotonics, optical sensing, and quantum communications. On the other hand, CsPb2Br5 nanowires have also attracted a lot of attention due to their unique water stability and controversial luminescent property. Here, the growth of CsPbBr3 nanocrystals on CsPb2Br5 nanowires is reported first by simply immersing CsPbBr3 powder into pure water, CsPbBr3−γ Xγ (X = Cl, I) nanocrystals on CsPb2Br5−γ Xγ nanowires are then synthesized for tunable light sources. Systematic structure and morphology studies, including in situ monitoring, reveal that CsPbBr3 powder is first converted to CsPb2Br5 microplatelets in water, followed by morphological transformation from CsPb2Br5 microplatelets to nanowires, which is a kinetic dissolution–recrystallization process controlled by electrolytic dissociation and supersaturation of CsPb2Br5. CsPbBr3 nanocrystals are spontaneously formed on CsPb2Br5 nanowires when nanowires are collected from the aqueous solution. Raman spectroscopy, combined photoluminescence, and SEM imaging confirm that the bright emission originates from CsPbBr3−γ Xγ nanocrystals while CsPb2Br5−γ Xγ nanowires are transparent waveguides. The intimate integration of nanoscale light sources with a nanowire waveguide is demonstrated through the observation of the wave guiding of light from nanocrystals and Fabry–Perot interference modes of the nanowire cavity.