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Lithium‐ion capacitor (LIC) is an advanced energy storage system due to the combination of high energy density and rapid charge–discharge capability. However, one of the challenges is to improve the specific capacitance and energy density of cathode at high power density. For activated carbon based cathode, the unique hierarchical porous structure and suitable graphitization are crucial for the improvement of the specific capacitance and energy density. Herein, a novel heating‐rate‐induced method is developed to prepare corncob‐derived activated carbons (C‐ACs) with high electrochemical performances. The as‐obtained C‐ACs possess large surface area (1154 m2 g−1), optimal hierarchical porous structure, and suitable graphitization. Particularly, optimal hierarchical porous structure contains not only the high energy storage of the micropores but also the high‐rate performance of the mesopores and macropores. The optimized C‐ACs‐8 electrode exhibits a specific capacitance of 158 F g−1 at 0.5 A g−1, exciting rate performance, and fast charge transfer capability. A lithium‐ion capacitor device based on C‐ACs‐8 cathode delivers a high energy density of 75 Wh kg−1 at power density of 562 W kg−1 and shows a long cycle life with 86.4% capacitance retention after 1000 cycles.

Metallized arrays of three-dimensional (3D) nanoarchitectures offer new and exciting prospects in nanophotonics and nanoelectronics. Engineering these repeating nanoarchitectures, which have dimensions smaller than the wavelength of the light source, enables in-depth investigation of unprecedented light–matter interactions. Conventional metal nanomanufacturing relies largely on lithographic methods that are limited regarding the choice of materials and machine write time and are restricted to flat patterns and rigid structures. Herein, we present a 3D nanoprinter devised to fabricate flexible arrays of 3D metallic nanoarchitectures over areas up to 4 × 4 mm2 within 20 min. By suitably adjusting the electric and flow fields, metal lines as narrow as 14 nm were printed. We also demonstrate the key ability to print a wide variety of materials ranging from single metals, alloys to multimaterials. In addition, the optical properties of the as-printed 3D nanoarchitectures can be tailored by varying the material, geometry, feature size, and periodic arrangement. The custom-designed and custom-built 3D nanoprinter not only combines metal 3D printing with nanoscale precision but also decouples the materials from the printing process, thereby yielding opportunities to advance future nanophotonics and semiconductor devices.