Recently, sensors that can imitate human skin have received extensive attention. Capacitive sensors have a simple structure, low loss, no temperature drift, and other excellent properties, and can be applied in the fields of robotics, human-machine interactions, medical care, and health monitoring. Polymer matrices are commonly employed in flexible capacitive sensors because of their high flexibility. However, their volume is almost unchanged when pressure is applied, and they are inherently viscoelastic. These shortcomings severely lead to high hysteresis and limit the improvement in sensitivity. Therefore, considerable efforts have been applied to improve the sensing performance by designing different microstructures of materials. Herein, two types of sensors based on the applied forces are discussed, including pressure sensors and strain sensors. Currently, five types of microstructures are commonly used in pressure sensors, while four are used in strain sensors. The advantages, disadvantages, and practical values of the different structures are systematically elaborated. Finally, future perspectives of microstructures for capacitive sensors are discussed, with the aim of providing a guide for designing advanced flexible and stretchable capacitive sensors via ingenious human-made microstructures.

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Tungsten disulphide (WS), which exhibits excellent saturable absorption properties, has attracted much attention in the applications of photonic devices. In this paper, WS is applied for the preparation of a saturable absorber (SA). Using the pulsed laser deposition (PLD) method, WS is deposited on the side surface of the tapered fiber. In order to obtain larger non-linearity of the SAs with evanescent wave interaction, the tapered fiber had a smaller waist diameter and longer fused zone. Gold film was deposited on the fiber-taper WS SAs to improve their reliability and avoid oxidation and corrosion. Employing the balanced twin-detector method, the modulation depth of the fiber-taper WS SAs was measured to be 17.2%. With the fiber-taper WS SA, a generated pulse with 246 fs duration and a 57 nm bandwidth was obtained at 1561 nm. The electrical signal to noise ratio was better than 92 dB. To our knowledge, the pulse duration was the shortest among the reported all-fiber lasers with transition metal dichalcogenide (TMD) SAs. These results indicate that fiber-taper WS SAs with smaller waist diameter and longer fused zone are promising photonic devices for ultrashort pulse generation in all-fiber lasers.

Polymer nanocomposites are a promising substitute for energy-storage dielectric materials in pulsed power systems. A barium titanate/polyvinylidenefluoride (BT/PVDF) nanocomposite is one of the most widely studied composite systems due to its comprehensive excellent dielectric properties. As the dielectric response of nanocomposites depends strongly on the size of the fillers, in this study, BT/PVDF nanocomposites with 92.3 nm, 17.8 nm and 5.9 nm BT particle fillers are fabricated to reveal the particle size effect of the fillers on the energy storage performance of the polymer nanocomposites. Owing to the small particle size and good dispersibility of the nanofillers, the nanocomposites with smaller BT particles show more uniform and denser microstructures. Moreover, with the increase of the filler fraction, the dielectric results indicate a breakdown strength enhancement in the nanocomposites with sub-20 nm BT fillers, which is quite different from the nanocomposites with normal fillers, and therefore leads to superior energy storage performance. This study provides experimental evidence for the application of ultrafine nanofillers in the nanocomposite for future energy storage systems.

The search for efficient and cost‐effective catalysts for bifunctional oxygen reduction and evolution reaction (ORR and OER) is highly demanded because of the sluggish four‐electron transfer involved redox reactions in Zn–air batteries (ZABs). Herein, (N, P) codoped CoS2 nanoclusters embedded inside TiO2 nanoporous films (denoted as N, P/CoS2@TiO2 NPFs) are synthesized as novel bifunctional ORR/OER catalysts for ZABs. The catalytic activity and stability are promoted by the (N, P)‐dopants due to the enhanced conductivity, increased active surface area, and facilitated reaction kinetics. The N, P/CoS2@TiO2 NPFs exhibit exceptional onset potentials of 0.91 and 1.41 V for ORR and OER, respectively. When used as cathodes in ZABs, the N, P/CoS2@TiO2 NPFs exhibit a reduced charge–discharge gap of 0.8 V at 10 mA cm−2 and a stable cycling performance over 130 h, surpassing the conventional Pt/C+IrO2 catalysts. Moreover, the assembled ZABs delivering a specific capacity of 610 mAh g−1 can be used for flexible devices. This work provides a path for the rational design of bifunctional electrocatalyst for ZABs.