Stretchable transparent electrodes (STEs) based on silver nanowires (AgNWs) have received considerable attention for a variety of flexible and wearable electronic/optoelectronic devices. Up to now, most efforts have focused on optimizing the STEs composed by a single AgNW conductive network. On the contrary, the structure−performance correlations of STEs formed by a hybrid percolative network which comprises the AgNW and a second conductive nanomaterial have rarely been discussed. In this work, we fabricated hybrid-type STEs by selecting three kinds of carbon nanotubes (CNTs) with different diameters to pair with three types of AgNWs with variable length-to-diameter ratios. The size effect of building blocks of the nine combinations on the optical, electrical, and mechanical properties of resultant STEs was thoroughly investigated. The results reveal that AgNWs and CNTs with smaller diameters are beneficial to achieve hybrid electrodes with a high transmittance and low haze. AgNWs with larger length-to-diameter ratios contribute hybrid STEs with lower sheet resistance by adding a suitable amount of CNTs. Importantly, the smaller differences in diameters of AgNWs and CNTs lead to more effective capillary-force-induced welding, which boosts both the conductivity and stretchability of STEs. An optimized AgNW/CNT hybrid electrode demonstrated a transmittance of 66.4% and a haze of 11.0% at a sheet resistance of 8.70 Ω sq. −1 which could endure a uniaxial tensile strain as large as 490%, while its resistance increased only 46.9% after experiencing 1000 cycles of 50% tensile strain. Alternating current electroluminescent devices based on such AgNW/ CNT hybrid STEs were also successfully developed, showing uniform and stable patterned luminescence.

Due to the inherent benefits of metallic Zn, aqueous Zn-based batteries have been deemed attractive candidates for next-generation energy storage devices with a high level of safety. Unfortunately, the reversibility...

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Direct writing of one-dimensional nanomaterials with large aspect ratios into customized, highly conductive, and high-resolution patterns is a challenging task. In this work, thin silver nanowires (AgNWs) with a length-to-diameter ratio of 730 are employed as a representative example to demonstrate a potent direct ink writing (DIW) strategy, in which aqueous inks using a natural polymer, sodium alginate, as the thickening agent can be easily patterned with arbitrary geometries and controllable structural features on a variety of planar substrates. With the aid of a quick spray-and-dry postprinting treatment at room temperature, the electrical conductivity and substrate adhesion of the written AgNWs-patterns improve simultaneously. This simple, environment benign, and low-temperature DIW strategy is effective for depositing AgNWs into patterns that are high-resolution (with line width down to 50 μm), highly conductive (up to 1.26 × 10 5 S/ cm), and mechanically robust and have a large alignment order of NWs, regardless of the substrate's hardness, smoothness, and hydrophilicity. Soft electroadhesion grippers utilizing as-manufactured interdigitated AgNWs-electrodes exhibit an increased shear adhesion force of up to 15.5 kPa at a driving voltage of 3 kV, indicating the strategy is very promising for the decentralized and customized manufacturing of soft electrodes for future soft electronics and robotics.

Wearable devices made of degradable fibers are rising stars in smart healthcare by virtue of their light weight, flexibility, and weavability. Silk protein is one promising platform for ideal fiber-type electronic devices due to its inherent biocompatibility and biodegradability. However, it remains a challenge for conductive silk-based fiber electronics to achieve high stretchability and skin-like softness. Here, hygroscopic calcium-modified MXene/silk nanocomposite fibers (Ca@MSNFs) are fabricated by decorating the wet-spun MXene/silk fibers with hygroscopic CaCl2, exhibiting 3.2 g g–1 water capture capacity at 90% relative humidity (RH), high stretchability (279.9%), degradability, repairability, and freeze-resistance (−18 °C). Furthermore, the Ca@MSNFs are assembled as humidity/strain sensors to monitor respiratory signals and body movements, showing great promise for the diagnosis of apnea syndrome and rehabilitation training. Moreover, Ca@MSNFs are degradable and do not cause pollution or environmental damage. Therefore, this work offers a promising strategy for constructing stretchable and degradable electronic devices for advanced healthcare applications.

Capillary-force-induced welding can effectively reduce the contact resistance between two silver nanowires (AgNWs) by merging the NW−NW junctions. Herein, we report a model for quantifying the capillary force between two nano-objects. The model can be used to calculate the capillary force generated between AgNWs and carbon nanotubes (CNTs) during water evaporation. The results indicate that the radius of one-dimensional nano-objects is crucial for capillary-force-induced welding. AgNWs with larger radii can generate a greater capillary force (F AgNW-AgNW ) at NW−NW junctions. In addition, for AgNW/CNT hybrid films, the use of CNTs with a radius close to that of AgNWs can result in a larger capillary force (F AgNW-CNT ) at NW−CNT junctions. The reliability of the model is verified by measuring the change in sheet resistance before and after capillary-force-induced welding of a series of AgNW and AgNW/CNT conductive films with varying radii.

In the rapidly growing area of high-frequency communications, polyimide films with ultralow dielectric constant and dielectric loss, adequate insulating strength, and recyclability are in high demand. Using a synthesized soluble fluorinated polyimide, a series of recyclable porous dielectric films with varying porosities were fabricated in this study through nonsolvent-induced phase separation. By manipulating the mass ratio of the binary solvent used to dissolve the polyimide, the shape, size, and size distribution of the pores generated throughout the polyimide matrix can be accurately regulated. The porosity and average pore size of the as-prepared porous films were adjustable between 71% and 33% and between 9.31 and 1.00 μm, respectively, which resulted in a variable dielectric constant of 1.51–2.42 (100 kHz) and electrical breakdown strength of 30.3–119.7 kV/mm. The porous sPI film with a porosity rate of 48% displayed a low dielectric constant of 2.48 at 10 GHz. Coupled with their superior thermal stability, mechanical characteristics, and recyclability, these porous polyimide films are highly promising for constructing high-frequency microelectronic devices.

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