A photoresponsive organogel surface (POS), which integrates characteristics of the photothermal property of Fe 3 O 4 nanoparticles and the low hysteresis feature of lubricant-infused organogels, is shown. A photothermally induced dynamic temperature gradient can be formed rapidly at the location of nearinfrared-light irradiation (NIR) on POS with suitable Fe 3 O 4 nanoparticles content. Thus, various droplets (e.g., water, glycerol, ethylene glycol, propylene glycol, and ethanol) can be transported effectively and nimbly (e.g., along desired trajectories with controllable velocity and direction, even run uphill and deliver solid particles). This work reveals a synergistic effect between the asymmetrical droplet deformation and the inside Marangoni flows, which forms a unique driving force for droplet transport with high efficiency. This finding offers insight into the design of novel responsive interface materials for droplet transportation, which would be significant for laboratory-on-a-chip contexts, mass transportation, and microengines.

A highly flexible and highly sensitive piezoresistive sensor was fabricated by using MXenes and polyvinyl butyral.

We propose a realization of perfect valley filters based on the chiral domain-wall channels between a quantum anomalous Hall insulator and a quantum valley Hall insulator. Uniquely, all these channels reside in the same valley and propagate unidirectionally, 100% valley-polarizing passing-by carriers without backscattering. The valley index, the chirality, and the number of the channels are protected by topological charges, controllable by external fields, and detectable by circular dichroism.

Heterostructure rough spindle‐knot microfibers (HRSFs) are fabricated via a flexible parallel‐nozzle microfluidic method. In this method, the bioinspired HRSF with a roughness gradient between spindle‐knots and joints, can be manufactured in large‐scale, and with which the size of the spindle‐knots and joints can be precisely adjusted by regulating flow rates. The HRSFs, fabricated with chitosan and calcium alginate, have strong mechanical properties and corrosion resistance in acid environment (pH = 5) and alkaline environment (pH = 9), respectively. More attractively, under controlled treatment conditions, the morphology of the spindle‐knots on the HRSFs can be effectively managed by changing the composite content of calcium chloride in the fluid. During the water collection process, tiny droplets of moisture can be captured on the surface of the HRSFs, subsequently, the droplets can coalesce and be transported from joint to spindle‐knot sections. It is demonstrated that the surface morphology of spindle‐knots directly influences the water collection efficiency, where a higher roughness gradient generates higher water collection efficiency. This parallel‐nozzle microfluidic technology provides a low‐cost and flexible method to manufacture high biocompatibility bioinspired rough spindle‐knot microfibers, which has many potential applications in large‐scale water collection, sustained drug release, and directional water collection.

The development of flexible capacitive pressure sensors has wide application prospects in the fields of electronic skin and intelligent wearable electronic devices, but it is still a great challenge to fabricate capacitive sensors with high sensitivity. Few reports have considered the use of interdigital electrode structures to improve the sensitivity of capacitive pressure sensors. In this work, a new strategy for the fabrication of a high-performance capacitive flexible pressure sensor based on MXene/polyvinylpyrrolidone (PVP) by an interdigital electrode is reported. By increasing the number of interdigital electrodes and selecting the appropriate dielectric layer, the sensitivity of the capacitive sensor can be improved. The capacitive sensor based on MXene/PVP here has a high sensitivity (~1.25 kPa−1), low detection limit (~0.6 Pa), wide sensing range (up to 294 kPa), fast response and recovery times (~30/15 ms) and mechanical stability of 10000 cycles. The presented sensor here can be used for various pressure detection applications, such as finger pressing, wrist pulse measuring, breathing, swallowing and speech recognition. This work provides a new method of using interdigital electrodes to fabricate a highly sensitive capacitive sensor with very promising application prospects in flexible sensors and wearable electronics.