High entropy alloys (HEAs) usually possess weak liquidity and castability, and considerable compositional inhomogeneity, mainly because they contain multiple elements with high concentrations. As a result, large-scale production of HEAs by casting is limited. To address the issue, the concept of eutectic high entropy alloys (EHEAs) was proposed, which has led to some promise in achieving good quality industrial scale HEAs ingots, and more importantly also good mechanical properties. In the practical large-scale casting, the actual composition of designed EHEAs could potentially deviate from the eutectic composition. The influence of such deviation on mechanical properties of EHEAs is important for industrial production, which constitutes the topic of the current work. Here we prepared industrial-scale HEAs ingots near the eutectic composition: hypoeutectic alloy, eutectic alloy and hypereutectic alloy. Our results showed that the deviation from eutectic composition does not significantly affect the mechanical properties, castability and the good mechanical properties of EHEAs can be achieved in a

Carbon nanotube (CNT) fiber has not shown its advantage as next-generation light-weight conductor due to the large contact resistance between CNTs, as reflected by its low conductivity and ampacity. Coating CNT fiber with a metal layer like Cu has become an effective solution to this problem. However, the weak CNT-Cu interfacial bonding significantly limits the mechanical and electrical performances. Here, we report that a strong CNT-Cu interface can be formed by introducing a Ni nanobuffer layer before depositing the Cu layer. The Ni nanobuffer layer remarkably promotes the load and heat transfer efficiencies between the CNT fiber and Cu layer and improves the quality of the deposited Cu layer. As a result, the new composite fiber with a 2 μm thick Cu layer can exhibit a superhigh effective strength >800 MPa, electrical conductivity >2 × 10 S/m, and ampacity >1 × 10 A/cm. The composite fiber can also sustain 10 000 times of bending and continuously work for 100 h at 90% ampacity.

In this study, a novel anion–cation method to synthesize highly emissive and stable diphase CsPbBr3@Cs4PbBr6 composite NCs has been developed.

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Colloidal halide perovskite (CHP) quantum dots (QDs)/nanocrystals (NCs) have superior optoelectronic properties, such as high optical absorption coefficient, high photoluminescence quantum yield (PLQY), tunable bandgap, composition‐related luminescence, and low manufacturing cost, which have been considered as promising low‐dimensional semiconductor materials. Profiting from these unique characteristics, CHP NCs could be widely used in various optoelectronic devices, including light‐emitting diodes (LEDs), photodetectors (PDs), solar cells (SCs), and lasers. Synthesis is the basis for the wide use of CHP NCs, which plays a vital role in the research, development and application of CHPs. Therefore, we summarize the recent synthetic strategies, and their influencing factors (e. g., the effects of ligands, and anion exchange). Besides, a summary of their optoelectronic applications is plainly mentioned. Finally, we make a brief prospect and summarize the current problems and possible solutions of this area.