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Bismaleimide resin (BMI) is a thermosetting resin with excellent properties. However, due to its poor toughness as a cured product, this paper uses hyperbranched polyimide (HBPI) and nano‐SiO2 in a synergistic manner to improve the performance of BMI. Isophorone diisocyanated tripolymer (IPDI trimer) and methyl nadic anhydride (MNA) were used to synthesize HBPI, and then we investigated the effect of the synergistic modification on the mechanical and thermal properties and the modification mechanism of HBPI and nano‐SiO2. The experiments showed that the most significant improvements were achieved at the addition of 40 and 3 wt% of HBPI and nano‐SiO2 respectively, with the impact strength of the materials increasing by 97.2%, fracture toughness indexes GIC and KIC increased by 36.7% and 34.6% respectively and glass transition temperature (Tg) was reduced. The SEM results showed that the nanoparticles were uniformly dispersed and further validated the synergistic modification mechanism. [ABSTRACT FROM AUTHOR]

2D stacking presents a promising avenue for creating periodic superstructures that unveil novel physical phenomena. While extensive research has focused on lateral 2D material superstructures formed through composition modulation and twisted moiré structures, the exploration of vertical periodicity in 2D material superstructures remains limited. Although weak van der Waals interfaces enable layer-by-layer vertical stacking, traditional methods struggle to control in-plane crystal orientation over large areas, and the vertical dimension is constrained by unscalable, low-throughput processes, preventing the achievement of global order structures. In this study, a supercell multiplying approach is introduced that enables high-throughput construction of 3D superstructures on a macroscopic scale, utilizing artificially stacked single-crystalline 2D multilayers as foundational repeating units. By employing wafer-scale single-crystalline 2D materials and referencing the crystal orientation of substrates, the method ensures precise alignment of crystal orientation within and across each supercell, thereby achieving controllable periodicity along all three axes. A centimeter-scale 3R-MoS₂ crystal is successfully constructed, comprising over 200 monolayers of single-crystalline MoS₂, through a bottom-up stacking process. Additionally, the approach accommodates the integration of amorphous oxide, enabling the assembly of 3D non-linear optical crystals with quasi-phase matching. This method paves the way for the bottom-up construction of macroscopic artificial 3D crystals with atomic plane precision, enabling tailored optical, electrical, and thermal properties and advancing the development of novel artificial materials and high-performance applications., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

2D materials, especially their monolayers, have garnered significant attention due to their unique electrical, optical and mechanical properties. Strain engineering is an effective way to modulate these properties. However, challenges remain in preventing slip or decoupling between the 2D material and the substrate due to the inherent weak van der Waals interactions. In this study, metal films are employed to apply strain to 2D materials. The high surface energy of metals helps to provide higher interaction forces, thereby improving strain transfer efficiency. Biaxial compressive and uniaxial tensile strain can be applied to monolayer MoS 2 , with the highest modulation rate of 542 and 161.7 meV/%, respectively, as characterized by photoluminescence (PL) spectra. Furthermore, this new approach can be broader to other 2D materials, such as WS 2 or WSe 2 , allowing for precise control over strain manipulation. The work introduces a promising new approach for efficient and controllable strain engineering of 2D materials., (© 2024 Wiley‐VCH GmbH.)