Wearable pressure sensors, which can perceive and respond to environmental stimuli, are essential components of smart textiles. Here, large-area all-textile-based pressure-sensor arrays are successfully realized on common fabric substrates. The textile sensor unit achieves high sensitivity (14.4 kPa ), low detection limit (2 Pa), fast response (≈24 ms), low power consumption (<6 µW), and mechanical stability under harsh deformations. Thanks to these merits, the textile sensor is demonstrated to be able to recognize finger movement, hand gestures, acoustic vibrations, and real-time pulse wave. Furthermore, large-area sensor arrays are successfully fabricated on one textile substrate to spatially map tactile stimuli and can be directly incorporated into a fabric garment for stylish designs without sacrifice of comfort, suggesting great potential in smart textiles or wearable electronics.

An electric field built inside a crystal was proposed to enhance photoinduced carrier separation for improving photocatalytic property of semiconductor photocatalysts. However, a static built-in electric field can easily be saturated by the free carriers due to electrostatic screening, and the enhancement of photocatalysis, thus, is halted. To overcome this problem, here, we propose sonophotocatalysis based on a new hybrid photocatalyst, which combines ferroelectric nanocrystals (BaTiO3) and semiconductor nanoparticles (Ag2O) to form an Ag2O-BaTiO3 hybrid photocatalyst. Under periodic ultrasonic excitation, a spontaneous polarization potential of BaTiO3 nanocrystals in responding to ultrasonic wave can act as alternating built-in electric field to separate photoinduced carriers incessantly, which can significantly enhance the photocatalytic activity and cyclic performance of the Ag2O-BaTiO3 hybrid structure. The piezoelectric effect combined with photoelectric conversion realizes an ultrasonic-wave-driven piezophototronic process in the hybrid photocatalyst, which is the fundamental of sonophotocatalysis.

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have been developed mainly based on TiO 2 nanoparticles with the effi ciency of more than 7% and have good stability under deformation. [ 11,12 ] Considering that solar energy is dependent on the weather and people stay most of a day indoors, mechanical energy could be an appropriate complement due to its universal availability. The triboelectric nanogenerator (TENG), [ 13,14 ] coupling the effect of contact-electrifi cation and electrostatic induction, has been demonstrated to be versatile in scavenging different types of mechanical energies, ranging from vibration, [ 15 ] wind, [ 16 ] water wave, [ 17 ] to human motions. [18][19][20] The abundant choice of materials and structure designs of the TENG enable its feasibility in integration with the E-textile for harvesting energy from human motions. Silver coating, [ 21 ] carbon nanotubes, [ 22 ] and carbon fi ber [ 23 ] were applied to textile fi bers, functioning as the electrode of the textile-based or fi ber-based TENG. In our previous studies, a woven TENG textile was realized by electroless deposition (ELD) of conformal and low-cost nickel coating to convert textile yarns/fabrics into conductive electrodes. [ 24 ] Despite these preliminary fi ndings, further research is still required to improve the output power of the TENG textile. Meanwhile, integration of the whole textile-based TENG and solar cell has seldom been found in literature, though several previous works have been reported integrated devices on fl at substrates. [ 25 ] Herein, we developed a grating-structured TENG fabric and its integration with FDSSCs so as to achieve a whole textile-based energy harvesting system. A route of laser-scribing masking and ELD Ni plating was fi rst proposed for the synthesis of conductive circuits/patterns on the textile. Interdigitated grating-structured TENG fabrics were then fabricated in aim to convert low-frequency human motion energy into high-frequency current outputs. By reducing the grating size, large improvements were achieved in the current amplitude and output power. Furthermore, FDSSCs and TENG fabrics were integrated together into a cloth as complementary power devices for harvesting both the energy of sunshine and human motions.The energy-generating device for wearable electronics or E-textiles should be versatile for fashionable and comfortable designs. Whereas, most of the previous reported TENGs for biomechanical energy-harvesting lack this versatility. The ideal TENG for E-textiles is in the form of fabrics. As schemed in Figure 1 a, a power-textile can be designed with the fabrics of the sleeve and underneath the arm (herein after noted as slider fabric and stator fabric, respectively) functioning as two pairs Electronic-textile (E-textile) or smart textile, which integrates multifunctional electronic/optoelectronic devices into fashionable/stylish clothing, holds great promise for the next growth of the market of wearable electronics. [ 1 ] Various components of electronic devices have been demonstrated in smart garments or fabrics, incl...

Electronic skin (e-skin) has been under the spotlight due to great potential for applications in robotics, human-machine interfaces, and healthcare. Meanwhile, triboelectric nanogenerators (TENGs) have been emerging as an effective approach to realize self-powered e-skin sensors. In this work, bioinspired TENGs as self-powered e-skin sensors are developed and their applications for robotic tactile sensing are also demonstrated. Through the facile replication of the surface morphology of natural plants, the interlocking microstructures are generated on tribo-layers to enhance triboelectric effects. Along with the adoption of polytetrafluoroethylene (PTFE) tinny burrs on the microstructured tribo-surface, the sensitivity for pressure measurement is boosted with a 14-fold increase. The tactile sensing capability of the TENG e-skin sensors are demonstrated through the characterizations of handshaking pressure and bending angles of each finger of a bionic hand during handshaking with human. The TENG e-skin sensors can also be utilized for tactile object recognition to measure surface roughness and discern hardness. The facile fabrication scheme of the self-powered TENG e-skin sensors enables their great potential for applications in robotic dexterous manipulation, prosthetics, human-machine interfaces, etc.

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Electrically conductive composites (ECCs) hold great promise in stretchable electronics because of their printability, facile preparation, elasticity, and possibility for large-area fabrication. A high conductivity at steady state and during mechanical deformation is a critical property for ECCs, and extensive efforts have been made to improve the conductivity. However, most of those approaches are exclusively functional to a specific polymer matrix, restricting their capability to meet other requirements, such as mechanical, adhesive, and thermomechanical properties. Here, we report a generic approach to prepare ECCs with conductivity close to that of bulk metals and maintain their conductivity during stretching. This approach iodizes the surfactants on the commercial silver flakes, and subsequent photo exposure converts these silver iodide nanoparticles to silver nanoparticles. The ECCs based on silver nanoparticle-covered silver flakes exhibit high conductivity because of the removal of insulating surfactants as well as the enhanced contact between flakes. The treatment of silver flakes is independent of the polymer matrix and provides the flexibility in matrix selection. In the development of stretchable interconnects, ECCs can be prepared with the same polymer as the substrate to ensure strong adhesion between interconnects and the substrate. For the fabrication of on-skin electrodes, a polymer matrix of low modulus can be selected to enhance conformal contact with the skin for reduced impedance.

Electroadhesion generates an adhesion force using an externally applied power source, which has versatile applications in robotics and material handling. In this study, a self-powered electroadhesion system using enhanced triboelectric nanogenerators (TENGs) to supply power for electroadhesion is presented. By introducing a triboelectric charge supplement channel, the open circuit voltage of the TENG can be significantly boosted by over 10 times, from ∼230 V to more than 3300 V for a single TENG unit, providing sufficiently high voltage for an electroadhesive patch to generate enough adhesion for practical use. The charge supplement channel takes effect through a replenishing mechanism for dissipated charges, maintaining an optimal charge distribution throughout TENG electrodes, which enables the highest open circuit voltage under given surface charge density and device configuration. The fabricated self-powered electroadhesion system shows the ability to manipulate objects of various materials via easy and straightforward operations, demonstrating a great potential for applications in material handling and robotics. Moreover, the voltage enhancement mechanism by the charge supplement channel could be extended to TENGs of other modes, which can provide reliable power sources for various applications that require a high voltage.