The development of highly sensitive pressure sensors with a low-cost and facile fabrication technique is desirable for electronic skins and wearable sensing devices. Here a low-cost and facile fabrication strategy to obtain multiscale-structured elastomeric electrodes and a highly sensitive and robust flexible pressure sensor is presented. The principles of spontaneous buckle formation of the PDMS surface and the embedding of silver nanowires are used to fabricate the multiscale-structured elastomeric electrode. By laminating the multiscale-structured elastomeric electrode onto the dielectric layer/bottom electrode template, the pressure sensor can be obtained. The pressure sensor is based on the capacitive sensing mechanism and shows high sensitivity (>3.8 kPa(-1)), fast response and relaxation time (<150 ms), high bending stability and high cycle stability. The fabrication process can be easily scaled up to produce pressure sensor arrays and they can detect the spatial distribution of the applied pressure. It is also demonstrated that the fingertip pressure sensing device can sense the pressure distribution of each finger, when grabbing an object.

High-performance all-inkjet-printed organic inverters are fabricated on flexible substrates. By introducing end-functionalized polystyrene on both surfaces of inkjet-printed source/drain Ag electrodes and poly(4-vinylphenol) dielectrics, organic-compatible and hydroxyl-free interfaces between those layers and 6,13-bis(triisopropylsilylethynyl)pentacene drastically reduce the interfacial trap and contact resistance. The resulting organic inverters show a full up-down switching performance and a high voltage gain of 19.8.

The rapid and dense assembly of solution-processed single-wall carbon nanotube (SWCNT) semiconducting films is the key enabling factor for their practical applications to large-area electronics and potentially, roll-to-roll based process development. In this study, we demonstrate a significant reduction in the assembly time for a commercial nanotube dispersion (95%-purified semiconducting SWCNT ink), whilst maintaining a high-quality film with better density, by adding a B0.1% volume ratio of nitric acid to the dispersion. A rapidly and densely assembled film was formed after deposition for less than 30 seconds, compared to more than several minutes in a commercial reference ink as previously reported by many research groups. The relationships among the zeta potential, pH concentration, and deposition time of the engineered dispersion were also investigated. The electrostatically weakened force of the ionic surfactants in the engineered inks leads to the rapid formation of densely packed SWCNT films, thereby enabling the fabrication of high-performance SWCNT thin film transistors (TFTs) with a field-effect mobility of 18.80 AE 2.08 cm 2 V À1 s À1 and on/off ratios of Z10 4 in a significantly reduced process time.

Herein, a simple and effective technique, “multidipping technique,” is implemented to rapidly form random networks of single‐walled carbon nanotubes (SWCNTs) used as a channel material in solution‐processed thin‐film transistors (TFTs). The multidipping process consists of repetition of dipping a substrate into a dispersed semiconducting SWCNT solution and rinsing the substrate between each dipping process. Compared with the conventional dipping method, this technique reduces total deposition time required to form high‐quality SWCNT networks by more than half and simultaneously improves the electrical performances of SWCNT TFTs. These phenomena are also comprehensively analyzed with experiments and microscopic images of the channel region, which well show morphology of the SWCNT networks. It is believed that the low‐temperature process and facile deposition method of SWCNT networks can provide a guideline for high‐throughput fabrication of high‐performance SWCNT TFT arrays in flexible active matrix sensor array and display applications.

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