Aligned ferroelectric single crystals of (3-pyrrolinium)(CdCl ) can be prepared from solution on top of aligned semiconducting C single crystals using an orthogonal solvent. Memory devices based on these ferroelectric/semiconductor bilayered heterojunctions exhibit much larger hysteresis compared with that of only C single crystals. More importantly, the introduction of the ferroelectric layer induces the memory window without dramatically reducing the charge mobility.

Morphing structures are often engineered with stresses introduced into a flat sheet by leveraging structural anisotropy or compositional heterogeneity. Here, we identify a simple and universal diffusion-based mechanism to enable a transient morphing effect in structures with parametric surface grooves, which can be realized with a single material and fabricated using low-cost manufacturing methods (e.g., stamping, molding, and casting). We demonstrate from quantitative experiments and multiphysics simulations that parametric surface grooving can induce temporary asynchronous swelling or deswelling and can transform flat objects into designed, three-dimensional shapes. By tuning the grooving pattern, we can achieve both zero (e.g., helices) and nonzero (e.g., saddles) Gaussian curvature geometries. This mechanism allows us to demonstrate approaches that could improve the efficiency of certain food manufacturing processes and facilitate the sustainable packaging of food, for instance, by creating morphing pasta that can be flat-packed to reduce the air space in the packaging.

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Aerial seeding can quickly cover large and physically inaccessible areas 1 to improve soil quality and scavenge residual nitrogen in agriculture 2 , for postfire reforestation 3-6 and wildland restoration 7,8 . However, it suffers from low germination rates due to the direct exposure of unburied seeds to harsh sunlight, wind, granivorous birds, and undesirable air humidity and temperature 1,9,10 . Inspired by Erodium seeds 11-14 , we design and fabricate self-drilling seed carriers, turning wood veneer into highly stiff (7.2 GPa when dry, and 1.2 GPa when wet) and hygromorphic bending or coiling actuators with an extremely large bending curvature (1854 m -1 ), 45 times larger than the literature values [15][16][17][18] . Our three-tailed carrier has an 80% drilling success rate on flat land after two triggering cycles due to the beneficial resting angle (25° -30°) of its tail anchoring, whereas the natural Erodium seed's success rate is 0%. Our carriers can carry payloads of different sizes and contents including biofertilizers and plant seeds as large as those of whitebark pine, which are 11 mm in length. We compare experiments with numerical simulation to elucidate the curvature transformation and actuation mechanisms to guide the design and optimization of the seed carriers. Our system will significantly improve the effectiveness of aerial seeding to relieve agricultural and environmental stresses, and has potential applications in energy harvesting, soft robotics and sustainable buildings.

Thermoplastic and Fused Deposition Modeling (FDM) based 4D printing are rapidly expanding to allow for space-and material-saving 2D printed sheets morphing into 3D shapes when heated. However, to our knowledge, all the known examples are either origami-based models with obvious folding hinges, or beam-based models with holes on the morphing surfaces. Morphing continuous double-curvature surfaces remains a challenge, both in terms of a tailored toolpathplanning strategy and a computational model that simulates it. Additionally, neither approach takes surface texture as a design parameter in its computational pipeline. To extend the design space of FDM-based 4D printing, in Geodesy, we focus on the morphing of continuous doublecurvature surfaces or surface textures. We suggest a unique tool path-printing thermoplastics along 2D closed geodesic paths to form a surface with one raised continuous doublecurvature tiles when exposed to heat. The design space is further extended to more complex geometries composed of a network of rising tiles (i.e., surface textures). Both design components and the computational pipeline are explained in the paper, followed by several printed geometric examples. CCS CONCEPTS • Computer-aided manufacturing, Interactive systems and tools;

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