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The nonlinear strain response of soft material–based snap-through systems enables amplified and accelerated force output. However, efficiency of snap-through energy release is challenging to improve because of the inherent trade-off between initial curvature and stiffness. Here, spatial programming of stiffness variation in the azobenzene-functionalized liquid-crystalline polymer (Azo-LCP) addresses this limitation and achieves efficient photomechanical jumping. Introduction of stiffness mismatch induced localized curvature, which preserved the initial curvature and simultaneously enhanced photomechanical strain responsivity. By programming for symmetry of stiffness variation, we achieved directional or vertical jumping via strategic placement of the rigid region, with corresponding stress accumulation behaviors corroborated by finite element simulations. Integration of patterned stiffness variation with geometric asymmetry enabled both vertical and horizontal jumping within a single structure, without compromising performance. This dual-mode jumper also demonstrated sequential and consecutive jumps under continuous light exposure. 

Abstract Bio‐enabled and bio‐mimetic nanomaterials represent functional materials, which use bio‐derived materials and synthetic components to bring the better of two, natural and synthetic, worlds. Prospective broad applications are flexibility and mechanical strength of lightweight structures, adaptive photonic functions and chiroptical activity, ambient processing and sustainability, and potential scalability along with broad sensing/communication abilities. Here, we summarize recent results on relevant functional photonic materials with responsive behavior under mechanical stresses, magnetic field, and changing chemical environment. We focus on recent achievements and trends in tuning optical materials' properties such as light scattering, absorption and reflection, light emission, structural colors, optical birefringence, linear and circular polarization for prospective applications in biosensing, optical communication, optical encoding, fast actuation, biomedical fields, and tunable optical appearance. 

Abstract The development of electronic devices from naturally derived materials is of enormous scientific interest. Melanin, a dark protective pigment ubiquitous in living creatures, may be particularly valuable because of its ability to conduct charges both electronically and ionically. However, device applications are severely hindered by its relatively poor electrical properties. Here, the facile preparation of conductive melanin composites is reported in which melanin nanoparticles (MNPs), directly extracted from squid inks, form electrically continuous junctions by tight clustering in a poly(vinyl alcohol) (PVA) matrix. Prepared as freestanding films and patterned microstructures by a series of precipitation, dry casting, and post‐thermal annealing steps, the percolated composites show electrical conductivities as high as 1.17 ± 0.13 S cm⁻¹at room temperature, which is the best performance yet obtained with biologically‐derived nanoparticles. Furthermore, the biodegradability of the MNP/PVA composites is confirmed through appetitive ingestion byZophobas morioslarvae (superworms). This discovery for preparing versatile biocomposites suggests new opportunities in functional material selections for the emerging applications of implantable, edible, green bioelectronics.