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Traditionally, slide-ring gels are stretchable but soft as a result of an elasticity-stretchability trade-off. Herein, we introduce a new approach to breaking this trade-off and creating reinforced slide-ring networks with mobile crosslinkers. Our approach involves the construction of a polyethylene glycol double-threaded γ-cyclodextrin-based pro-slide-ring crosslinker that serves as a modular component for 3D printing and copolymerization. The resulting crystalline-domain-reinforced slide-ring hydrogels, or CrysDoS-gels, exhibit both high elasticity and high stretchability. The modular synthesis allows for high-throughput synthesis of CrysDoS-gels, generating a large amount of data for structure-property analysis. By employing data science techniques, such as machine learning and linear regression, not only were we able to identify which chemical components influence the mechanical properties of CrysDoS-gels, but this analysis also aided in the discovery of better-performing CrysDoS-gels. Finally, we demonstrate the potential application of the newly discovered CrysDoS-gels as sensing devices by 3D printing them as stress sensors with high sensitivity and a broad detection range. 

We report modulation of exciton dissociation dynamics in quantum dots (QD) connected with photochromic molecules. Our results show that switching the configuration of photochromic molecules changes the inter-QD potential barrier height which has a major impact on the charge tunnelling and exciton dissociation. The switching of the dominant exciton decay pathway between the radiative recombination and exciton dissociation results in switchable photoluminescence intensity from QDs. Implications of our findings for optical memory and optical computing applications are discussed. 

We use microcrystal electron diffraction (MicroED) to determine structures of three organic semiconductors, and show that these structures can be used along with grazing-incidence wide-angle X-ray scattering (GIWAXS) to understand crystal packing and orientation in thin films. Together these complimentary techniques provide unique structural insights into organic semiconductor thin films, a class of materials whose device properties and electronic behavior are sensitively dependent on solid-state order. 

Abstract The development of integrated systems that mimic the multi‐stage stiffness change of marine animals such as the sea cucumber requires the design of molecularly tailored structures. Herein, we used an integrated biomimicry design to fabricate a sea cucumber mimic using sidechain polypseudorotaxanes with tunable nano‐to‐macroscale properties. A series of polyethylene glycol (PEG)‐based sidechain copolymers were synthesized to form sidechain polypseudorotaxanes with α‐cyclodextrins (α‐CDs). By tailoring the copolymers’ molecular weights and their PEG grafting densities, we rationally tuned the sizes of the formed polypseudorotaxanes crystalline domain and the physical crosslinking density of the hydrogels, which facilitated 3D printing and the mechanical adaptability to these hydrogels. After 3D printing and photo‐crosslinking, the obtained hydrogels exhibited large tensile strain and broad elastic‐to‐plastic variations upon α‐CD (de)threading. These discoveries enabled a successful fabrication of a sea cucumber mimic, demonstrating multi‐stage stiffness changes. 

We present a design strategy for fabricating ultrastable phase-pure films of formamidinium lead iodide (FAPbI₃) by lattice templating using specific two-dimensional (2D) perovskites with FA as the cage cation. When a pure FAPbI₃precursor solution is brought in contact with the 2D perovskite, the black phase forms preferentially at 100°C, much lower than the standard FAPbI₃annealing temperature of 150°C. X-ray diffraction and optical spectroscopy suggest that the resulting FAPbI₃film compresses slightly to acquire the (011) interplanar distances of the 2D perovskite seed. The 2D-templated bulk FAPbI₃films exhibited an efficiency of 24.1% in a p-i-n architecture with 0.5–square centimeter active area and an exceptional durability, retaining 97% of their initial efficiency after 1000 hours under 85°C and maximum power point tracking. 

Abstract Organic semiconductors (OSCs) have shown great promise in a variety of applications. Although solution processing of OSCs has resulted in high‐quality films, exquisite control of structural development to minimize defect formation during large‐scale fabrication remains formidable. Compounding this challenge is the use of halogenated organic solvents, which poses significant health and environmental hazards. However, the solvent‐free techniques introduced thus far impose additional limitations on solidification kinetics; the resulting OSC thin films are often more defective than those processed from solution. Here, a solvent‐free technique is reported to prepare OSC membranes with centimetric crystalline domains. Leveraging the tendency for liquid crystalline materials to preferentially orient, OSCs are “prealigned” by depositing them from the melt over a metal frame to form a freely suspended membrane. Crystallization from this prealigned phase affords membranes with unprecedented structural order across macroscopic distances. Field‐effect transistors comprising membranes of dioctyl[1]‐benzothieno[3,2‐b][1]benzothiophene (C8BTBT) and didodecyl[1]‐benzothieno[3,2‐b][1]benzothiophene (C12BTBT) having centimeter‐sized domains as active layers exhibit a hole mobility of ≈8.6 cm²V⁻¹s⁻¹, superseding the mobility of any transistors whose active layers are deposited from melt. This technique is scalable to yield membranes with large crystalline domains over wafer dimensions, making it amenable for broad applications in large‐area organic electronics.