All-solid-state, flexible, symmetric, and asymmetric microsupercapacitors are fabricated by a simple method in a scalable fashion from laser-induced graphene on commercial polyimide films, followed by electrodeposition of pseudocapacitive materials on the interdigitated in-plane architectures. These microsupercapacitors demonstrate comparable energy density to commercial lithium thin-film batteries, yet exhibit more than two orders of magnitude higher power density with good mechanical flexibility.

In recent years, organic resistive memory devices in which active organic materials possess at least two stable resistance states have been extensively investigated for their promising memory potential. From the perspective of device fabrication, their advantages include simple device structures, low fabrication costs, and printability. Furthermore, their exceptional electrical performances such as a nondestructive reading process, nonvolatility, a high ON/OFF ratio, and a fast switching speed meet the requirements for viable memory technologies. Full understanding of the underlying physics behind the interesting phenomena is still challenging. However, many studies have provided useful insights into scientific and technical issues surrounding organic resistive memory. This Feature Article begins with a summary on general characteristics of the materials, device structures, and switching mechanisms used in organic resistive devices. Strategies for performance enhancement, integration, and advanced architectures in these devices are also presented, which may open a way toward practically applicable organic memory devices.

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The modification of graphene-based materials is an important topic in the field of materials research. This study aims to expand the range of properties for laser-induced graphene (LIG), specifically to tune the hydrophobicity and hydrophilicity of the LIG surfaces. While LIG is normally prepared in the air, here, using selected gas atmospheres, a large change in the water contact angle on the as-prepared LIG surfaces has been observed, from 0° (superhydrophilic) when using O or air, to >150° (superhydrophobic) when using Ar or H . Characterization of the newly derived surfaces shows that the different wetting properties are due to the surface morphology and chemical composition of the LIG. Applications of the superhydrophobic LIG are shown in oil/water separation as well as anti-icing surfaces, while the versatility of the controlled atmosphere chamber fabrication method is demonstrated through the improved microsupercapacitor performance generated from LIG films prepared in an O atmosphere.

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Flexible materials and devices could be exploited in light-emitting diodes, electronic circuits, memory devices, sensors, displays, solar cells and bioelectronic devices. Nanoscale elements such as thin films, nanowires, nanotubes and nanoparticles can also be incorporated into the active films of mechanically flexible devices. Large-area devices containing extremely thin films of molecular materials represent the ultimate scaling of flexible devices based on organic materials, but the influence of bending and twisting on the electrical and mechanical stability of such devices has never been examined. Here, we report the fabrication and characterization of two-terminal electronic devices based on self-assembled monolayers of alkyl or aromatic thiol molecules on flexible substrates. We find that the charge transport characteristics of the devices remain stable under severe bending conditions (radius ≤ 1 mm) and a large number of repetitive bending cycles (≥1,000). The devices also remain reliable in various bending configurations, including twisted and helical structures.

Organic memory: Our three‐dimensionally (3D) stacked 8 × 8 cross‐bar array organic resistive memory devices showed non‐volatile memory switching behavior, in which individual memory cells in the different layers can be independently controlled and monitored. The 3D stackable organic memory devices will enable achieving highly integrable organic memory devices and other organic‐based electronics with much increased cell density.

Organic nonvolatile memory devices fabricated on flexible substrates showed rewritable and nearly consistent switching characteristics, regardless of the bending circumstances. This stable memory performance with bending stress is a promising property for the practical memory devices in future flexible electronics.