It is usually accepted that good thermoelectric (TE) materials should be narrow-gap semiconductors. Here we show an example that the tetrahedrally bonded stannite compound Cu2ZnSnSe4 with a band gap of 1.44 eV can also exhibit a high figure of merit at intermediate temperature. The highly distorted structure strives for the relatively low thermal conductivity, and the tunability of the electrical properties were demonstrated through doping. The maximum ZT of Cu2ZnSn0.90In0.10Se4 reaches 0.95 at 850 K. This work may open a way for exploring high-performance TE materials with the family of widely existing tetrahedrally bonded semiconductors.

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High sensitivity and wide linear range are core performances for flexible pressure sensors in practical applications. Due to the trade‐off between sensitivity and linear range, developing high‐performance flexible pressure sensors with both high sensitivity and wide linear range through a facile method is still a great challenge. Herein, a synergistically microstructured flexible pressure sensor with fibrous and microdomed (FMD) structure composed of a fibrous conductive layer sandwiched between a microdome‐structured PDMS layer and an interdigital electrode is proposed. Ascribed to the synergistic effect of the FMD structure possessing multiple deformations, the resistance of the sensor varies sensitively and continuously under pressure. Consequently, the pressure sensors perform a high sensitivity (6.31 kPa−1), an ultrawide linear range (4.6 Pa–800 kPa), short response time (72 ms) and relaxation time (88 ms), and remarkable stability during 10 000 loading/unloading cycles under 127.4 kPa. These high performances allow the sensors to detect full‐range human psychological signals from low to high pressures, such as pulse, phonation, joint moments, and plantar pressure. Moreover, the synergistically microstructured sensors can be integrated into large‐area and crosstalk‐free sensor array to map the spatial pressure distribution, demonstrating their viable applications in personal physiological parameters monitoring and human–machine interfaces.

We report an all-atom molecular dynamics study of the structures and dynamics of salty water droplets on a silicon surface under the influence of applied electric field. Our simulation results support ion-specific effects on the elongation dynamics of salty nanodroplets, induced by the field. This feature has not been explored up to now in monovalent salts. Nevertheless, the importance of ion-specific effects is widely confirmed in biological and colloidal systems. In particular, the increase of salt concentration enhances the effect of the nature of ions on the wetting properties of droplets. In the presence of electric field (0.05 V Å), a complete spreading is implemented in a short time for different droplets at a concentration of 1 M, and the droplet morphology is stable, observed at long time scales. However, a higher salt concentration of 4 M considerably suppresses the spreading process owing to the increase of surface tension. It was found that the NaCl droplet shows deformation oscillations along the external field, but cannot fully wet the substrate surface. By contrast, the CsCl droplet reaches complete elongation rapidly and adopts a steady strip shape. The KCl droplet undergoes frequent transitions between breakup and connection. Additionally, the droplets can be elongated only when the electric field strength exceeds a threshold value. The dipole orientation of interfacial water and the ionic diffusion exhibit ion-specific dependences, but the hydrogen bond network is scarcely disturbed, excluding a concentration-dependent effect.