Digital 3D printing with a shape memory polymer is utilized to create mechanical metamaterials exhibiting dramatic and reversible changes in stiffness, geometry, and functions.

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Artificial structural colors have attracted more and more attention due to their high photostability, low toxicity, and brilliant colors. Inkjet printing of photonic crystals or amorphous photonic structures can realize large-scale structural color patterns, while plasma printing of metals can achieve high-precision color images. However, still no method is available to fabricate structural color patterns on both a large scale and with high precision. Here, nanosphere-aggregation-induced reflection (NAIR) is first theoretically and experimentally demonstrated and vivid full-spectrum structural color can be generated based on NAIR. Dramatically different from photonic crystals, the accumulation of only a few monodisperse dielectric spheres with an appropriate refractive index and diameter can produce bright structural colors, which makes high resolution possible. By introducing commercial inkjet printers, this aggregate structure can be constructed at high speed in a large scale. Importantly, the color mixing is easily performed by simultaneously applying spheres with different sizes, which allow us to sophisticatedly control the generated color. The demonstrated NAIR printing paves the way toward a full-spectrum, large-scale, and high-precision structural color, offering great potential for daily commercial utilization.

Wind energy is one of the most promising renewable energy sources, but harvesting low frequency breeze wind energy is hardly achieved using traditional electromagnetic generators (EMGs). Triboelectric nanogenerators (TENGs) provide a new approach for large‐scale collection of distributed breeze wind energy (usually 3.4–5.4 m s−1). Herein, by coupling the TENG and EMG, a swing‐structured hybrid nanogenerator with improved performance and durability is designed. The dielectric brush and air gap designs can minimize the material wear and continuously supply the tribo‐charges. Under external triggering, systematic comparisons are made about the output characteristics of TENG and EMG. The rectified peak power and average power of TENG are respectively, 60 and 635 times higher than those of EMG at moderate coil turn numbers, showing that TENG is much more effective than EMG for harvesting low‐frequency distributed energy (high entropy energy). Furthermore, the hybrid nanogenerator and array device are hung on tree branches to demonstrate the effective harvesting of breeze wind energy, delivering total rectified peak power densities of 2.07 and 1.94 W m–3 for single and array devices, respectively. The applications of powering portable electronics reveal the huge prospects of hybrid nanogenerator in self‐powered environmental monitoring toward forest/park fire warning systems.