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A major challenge accompanying the booming next-generation soft electronics is providing correspondingly soft and sustainable power sources for driving such devices. Here, we report stretchable triboelectric nanogenerators (TENG) with dual working modes based on the soft hydrogel-elastomer hybrid as energy skins for harvesting biomechanical energies. The tough interfacial bonding between the hydrophilic hydrogel and hydrophobic elastomer, achieved by the interface modification, ensures the stable mechanical and electrical performances of the TENGs. Furthermore, the dehydration of this toughly bonded hydrogel-elastomer hybrid is significantly inhibited (the average dehydration decreases by over 73%). With PDMS as the electrification layer and hydrogel as the electrode, a stretchable, transparent (90% transmittance), and ultrathin (380 μm) single-electrode TENG was fabricated to conformally attach on human skin and deform as the body moves. The two-electrode mode TENG is capable of harvesting energy from arbitrary human motions (press, stretch, bend, and twist) to drive the self-powered electronics. This work provides a feasible technology to design soft power sources, which could potentially solve the energy issues of soft electronics.

Soft ionic conductors show great promise in multifunctional iontronic devices, but currently utilized gel materials suffer from liquid leakage or evaporation issues. Here, a dry ion‐conducting elastomer with dynamic crosslinking structures is reported. The dynamic crosslinking structures endow it with combined advantageous properties simultaneously, including high ionic conductivity (2.04 × 10−4 S cm−1 at 25 °C), self‐healing capability (96% healing efficiency), stretchability (563%), and transparency (78%). With this ionic conductor as the electrode, two soft iontronic devices (electroluminescent devices and triboelectric nanogenerator tactile sensors) are realized with entirely self‐healing and stretchable capabilities. Due to the absence of liquid materials, the dry ion‐conducting elastomer shows wide operational temperature range, and the iontronic devices achieve excellent stability. These findings provide a promising strategy to achieve highly conductive and multifunctional soft dry ionic conductors, and demonstrate their great potential in soft iontronics or electronics.

The viable application of soft electronics/robotics relies on the development of power devices which are desired to be flexible, deformable, or even self-healable. We report here a shape-adaptive, self-healable triboelectric nanogenerator (SS-TENG) for harvesting biomechanical energies. The use of a viscoelastic polymer, normally known as Silly Putty, as the electrification material and as the matrix of a carbon-nanotube-filled composite (CNT-putty) electrode endows the SS-TENG the capability of adapting to arbitrary irregular surfaces and instantaneous healing from mechanical damage (almost completely recovered in 3 min without extra stimuli). Furthermore, the output performances of the SS-TENG have also been significantly improved because (i) the ideal soft contact is achieved at the solid–solid interfaces for more effective contact electrification and (ii) the introduced cation dopants make the putty even more tribo-negative than polytetrafluoroethylene. The SS-TENG can be adhered to any curvy surface, tailored, and reshaped into arbitrary configurations and utilized as a power supply for small electronics, suggesting promising applications in soft electronics/robotics in the future.

Rapid growth of electronic textile increases the demand for textile-based power sources, which should have comparable lightweight, flexibility, and comfort. In this work, a self-charging power textile interwoven by all-yarn-based energy-harvesting triboelectric nanogenerators (TENG) and energy-storing yarn-type asymmetric supercapacitors (Y-ASC) is reported. Common polyester yarns with conformal Ni/Cu coating are utilized as 1D current collectors in Y-ASCs and electrodes in TENGs. The solid-state Y-ASC achieves high areal energy density (≈78.1 µWh cm −2 ), high power density (14 mW cm −2 ), stable cycling performance (82.7% for 5000 cycles), and excellent flexibility (1000 cycles bending for 180°). The TENG yarn can be woven into common fabrics with desired stylish designs to harvest energy from human daily motions at high output (≈60 V open-circuit voltage and ≈3 µA short-circuit current). The integrated self-charging power textile is demonstrated to power an electronic watch without extra recharging by other power sources, suggesting its promising applications in electronic textiles and wearable electronics.platforms for fabricating soft TENGs for the following reasons: (1) numerous microfibers in yarns/fabrics can provide tremendous surface areas for triboelectrification; (2) most commonly used materials (nylon, polyester, silk, etc.) are excellent in electrification. Therefore, self-charging power textiles, capable of generating and storing electricity simultaneously, can possibly be realized in one single fabric, so that the lightweight/flexibility of an E-textile is maintained with less or no extra battery recharging or replacement. Xiao et al. first demonstrated an integrated self-powered system with fiber-based supercapacitors and a TENG. [11] Pu et al. later proposed an all-yarn based self-charging power textile. [8] Wen et al. also developed a self-charging textile which can simultaneously harvest solar energy and random body motion energies and then store them in an energy storage unit. [12] Kwak et al. further showed knitted textile nanogenerators that can be stretched. [13] Recent reports have also realized integrated energy textile with various materials and synthesis routes, [2b,10d,e] but the outputs of both energy-harvesting TENG textile and energy-storing yarn-supercapacitors still need to be improved.Here, we report a self-charging power textile enabled by yarn-based TENGs (Y-TENGs) as energy-harvesting devices and yarn asymmetric supercapacitors (Y-ASC) as the energy-storage unit. Conductive yarns were first fabricated with Ni and Cu films coated successively on the surface of common polyester yarns. The yarn supercapacitor consists of a negative yarn electrode with hydrothermally self-assembled rGO/CNT coating and a positive electrode of electroplated Ni-Co bimetallic oxyhydroxide (NiCo BOH) coating. The solid-state Y-ASC exhibited high areal energy density (≈78.1 µWh cm −2 ), high power density (14 mW cm −2 ), high flexibility (1000 cycles bending for 180°), and stable cycling performance ...

The integration between energy-harvesting and energy-storage devices into a self-charging power unit is an effective approach to address the energy bottleneck of wearable/portable/wireless smart devices. Herein, we demonstrate a stretchable coplanar self-charging power textile (SCPT) with triboelectric nanogenerators (TENGs) and microsupercapacitors (MSCs) both fabricated through a resist-dyeing-analogous method. The textile electrodes maintain excellent conductivity at 600% and 200% tensile strain along course and wale directions, respectively. The fabric in-plane MSC with reduced graphene oxides as active materials reaches a maximum areal capacitance of 50.6 mF cm–2 at 0.01 V s–1 and shows no significant degradation at 50% of tensile strain. The stretchable fabric-based TENG can output 49 V open-circuit voltage and 94.5 mW m–2 peak power density. Finally, a stretchable coplanar SCPT with one-batch resist-dyeing fabrication is demonstrated for powering small electronics intermittently without extra recharging. Our approach is also compatible with conventional textile processing and suggests great potential in electronic textiles and wearable electronics.

Distributed renewable kinetic energies are ubiquitous but with irregular amplitudes and frequencies, which, as one category of “high-entropy” energies, are crucial for next-generation self-powered electronics. Herein, we present a flexible waterproof dual-mode textile triboelectric nanogenerator (TENG), which can simultaneously scavenge multiple “high-entropy” kinetic energies, including human motions, raindrops, and winds. A freestanding-mode textile TENG (F-TENG) and a contact-separation-mode textile TENG (CS-TENG) are integrated together. The structure parameters of the textile TENG are optimized to improve the output performances. The raindrop can generate a voltage of up to ∼4.3 V and a current of about ∼6 μA, while human motion can generate a voltage of over 120 V and a peak power density of ∼500 mW m–2. The scavenged electrical energies can be stored in capacitors for powering small electronics. Therefore, we demonstrated a facile preparation of a TENG-based energy textile that is highly promising for kinetic energy harvesting and self-powered electronics.

The progress of electronic textiles relies on the development of sustainable power sources without much sacrifice of convenience and comfort of fabrics. Herein, we present a rechargeable textile alkaline Zn microbattery (micro-AZB) fabricated by a process analogous to traditional resist-dyeing techniques. Conductive patterned electrodes are realized first by resist-aided electroless/electrodeposition of Ni/Cu films. The resulting coplanar micro-AZB in a single textile, with an electroplated Zn anode and a Ni 0.7 Co 0.3 OOH cathode, achieves high energy density (256.2 Wh kg −1 ), high power density (10.3 kW kg −1 ), and stable cycling performances (82.7% for 1500 cycles). The solid-state micro-AZB also shows excellent mechanical reliability (bending, twisting, tailoring, etc.). The improved reversibility and cyclability of textile Zn electrodes over conventional Zn foils are found to be due to the significantly inhibited Zn dendrite growth and suppressed undesirable side reactions. This work provides a new approach for energy-storage textile with high rechargeability, high safety, and aesthetic design versatility.