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Atmospheric water vapor is an abundant and renewable resource that can alleviate growing water scarcity. Hybrid hydrogel desiccants composed of hygroscopic salts hold significant promise for atmospheric water harvesting (AWH) due to their increased capacity for water uptake. Thus far, many efforts in fabricating these desiccants require multistep processes, where the salt impregnation is achieved post-hydrogel fabrication. Here, we develop a scalable wet spinning methodology using aramid nanofibers (ANFs) to template and coagulate hydroxypropyl cellulose (HPC) into filaments in a coagulation bath consisting of water and lithium chloride (LiCl). HPC serves as the matrix to retain the captured water vapor, and later releases it upon heating. ANFs serve as the physical cross-linker between HPC, allowing for wet spinning at a speed up to 61 m h–1. The composite filaments achieve up to 0.55 g g–1 water uptake at 30% relative humidity (RH) and 21 °C, reaching 80% saturation in 40 min. With a lower critical solution temperature of 39 °C, the desiccant filaments can release up to 72% of the captured water at 60 °C after 30 min. In an AWH chamber, the filaments can achieve daily water production of 5.21 L kg–1 day–1 at 30% RH and 21 °C. 

Abstract Materials that exhibit varied optical responses to different modes of mechanical stimuli are attractive for complex sensing and adaptive functionalities. However, most mechanochromic materials are fabricated from films or fibers with limited actuation modes. Here, hollow tubes of a symmetric sheath are created using cholesteric liquid crystal elastomers (CLCEs) at the sub‐millimeter scale. The oligomeric precursor is sheared in an elastomeric microchannel to form uniform thickness, overcoming gravity effect and Plateau‐Rayleigh instability. In addition, the coloration is achieved to be faster and have higher reflectivity compared to that of solid fibers. The tube can undergo axial, circumferential, and radial strains upon extension and inflation. The combination of molecular anisotropy and geometry of the tube enables highly sensitive mechanochromic responses in both azimuthal and axial directions: inflation causes red‐to‐violet shift (≈220 nm) at a circumferential strain of 0.57. The inflation of a bent tube generates another mechanochromic mode with a higher sensitivity to strain. Finally, display of 26 alphabets is achieved using 5 tubes, of which the positions can be reconfigured, and curvature‐dependent 3D photonic skins are demonstrated from tubes wrapped around 3D objects. The multi‐mode mechanochromic tubes will find applications for soft robotics, adaptive displays, wearable sensors, and spectrometers. 

Abstract Cellular solids composed of a network of interconnected pores offer low‐density and high strength‐to‐weight ratio as exemplified by wood, bones, corks, and shells. However, the slender edges and low connectivity of the structs in cellular lattices make them vulnerable to buckle, fracture, or collapse. Here, by taking advantage of the continuity of a thin film that can follow curvatures and dissipate energy, shellular materials are created by dip coating a wireframe of the primitive triply periodic minimal surface (TPMS) with an aqueous solution of lyotropic liquid crystalline graphene oxide (GO)/polymer composites. Regulated by surface tension, GO nanosheets align on the polymer soap film as the stress builds up during drying. When the wireframe mesh density is low, the shellular material is film‐dominated, demonstrating superior mechanical strength (384.30 Nm kg⁻¹) and high specific energy absorption (1.59 kJ kg⁻¹) yet lightweight (equivalent density, 0.063 g cm⁻³), with an energy absorption rate comparable to that of carbon nanotube‐based lattices but a lower equivalent density. The study offers insights into designing lightweight yet high‐strength structural materials that also function as impact energy absorbers.