An All‐Freeze‐Casting Strategy to Design Typographical Supercapacitors with Integrated Architectures

Abstract

The emergence of flexible and wearable electronics has raised the demand for flexible supercapacitors with accurate sizes and aesthetic shapes. Here, a strategy is developed to prepare flexible all-in-one integrated supercapacitors by combining all-freeze-casting with typography technique. The continuous seamless connection of all-in-one supercapacitor devices enhances the load and/or electron transfer capacity and avoids displacing and detaching between their neighboring components at bending status. Therefore, such a unique structure of all-in-one integrated devices is beneficial for retaining stable electrochemical performance at different bending levels. More importantly, the sizes and aesthetic shapes of integrated supercapacitors could be controlled by the designed molds, like type matrices of typography. The molds could be assembled together and typeset randomly, achieving the controllable construction and series and/or parallel connection of several supercapacitor devices. The preparation of flexible integrated supercapacitors will pave the way for assembling programmable all-in-one energy storage devices into highly flexible electronics.

Freeze Casting: From Low‐Dimensional Building Blocks to Aligned Porous Structures—A Review of Novel Materials, Methods, and Applications

“…Of further note, in addition to monolithic freeze‐cast scaffolds, macrostructures such as beads/microspheres, [ 29 ] fibers, [ 8f,30 ] meshes, [ 10b,31 ] films, [ 32 ] membranes [ 10c,33 ] and other complex morphologies [ 34 ] with aligned porous microstructures can be achieved by combining freeze‐casting with other materials processing or shaping routes such as electrospraying, [ 29e ] electrospinning, [ 30b,35 ] extrusion, [ 8f ] tape‐casting, [ 36 ] or additive manufacturing [ 37 ] during the solidification process. As the adoption of freeze casting techniques progresses, these forming techniques are the subject of growing interest towards diverse applications as discussed in a subsequent section of this review.…”

Laser‐Irradiated Holey Graphene‐Supported Single‐Atom Catalyst towards Hydrogen Evolution and Oxygen Reduction

“…[15,16] Similarly, a top-down approach is usually used to convert metal nanoparticles into SAC; however, high-temperature treatments demolish the support structure, which affects the supporting material's conductivity and leads to a drop in catalytic performance. [17] It is urgent to develop a sustainable synthesis approach that could be environmentally friendly and; cost-effective in ambient conditions to convert bulk metals species to SAC.…”

A Flexible Quasi‐Solid‐State Bifunctional Device with Zinc‐Ion Microbattery and Photodetector

“…Raman spectrum also confirmed the existence of PANI layer on Au arrays (Figure S3). The characteristic Raman peaks of PANI are observed at 1163 (bending vibrations of C−H in quinoid rings), 1479 and 1588 (stretching vibration of C=C in quinoid and benzenoid rings), 1214 (bending vibration of C−H in benzenoid rings) and 1334 cm −1 (stretching vibration of C−N + ) . The peak at 1334 cm −1 suggests that the PANI was doped.…”

“…The characteristic Raman peaks of PANI are observed at 1163 (bending vibrations of CÀ H in quinoid rings), 1479 and 1588 (stretching vibration of C=C in quinoid and benzenoid rings), 1214 (bending vibration of CÀ H in benzenoid rings) and 1334 cm À 1 (stretching vibration of CÀ N + ). [13] The peak at 1334 cm À 1 suggests that the PANI was doped. Cross-sectional scanning electron microscopy (SEM) image shows that the thickness of PANI layer is about 0.8 μm when the cycle number is 100 ( Figure S4a).…”