Recently emerged electronic skins with applications in on-body sensing and human-machine interfaces call for the development of high-performance skin-like electrodes. In this work, we report a highly robust, transparent, and breathable epidermal electrode composed of a scaffold-reinforced conductive nanonetwork (SRCN). Solution-dispersed Ag nanowires, through facile vacuum filtration, are embedded into a scaffold made of polyamide nanofibers. Optical transmittance of 84.9% at 550 nm wavelength is achieved at a significantly low sheet resistance of 8.2 Ω sq. The resistance of the SRCN only slightly increases by less than 0.1% after being bent for 3000 cycles at the maximum curvature of 300 m and by less than 1.5% after being dipped in saline solution for 2500 cycles. The excellent robustness is attributed to the reinforcement from the nanofiber-based scaffold as a backbone that maintains the connections among the Ag nanowires by undertaking most of the loaded stress. The SRCN not only forms tight and conformal bonding with the target surface but also allows the evaporation of perspiration, making it suitable as an epidermal electrode for long-time use. Furthermore, fine and clean-cut circuit patterns with a line width on the micrometer scale can be readily prepared, paving the way for fabricating sophisticated functional electronic skins.

Triboelectrification-induced electroluminescence converts dynamic motion into light emission. Tribocharges resulting from the relative mechanical interactions between two dissimilar materials can abruptly and significantly alter the surrounding electric potential, exciting the electroluminescence of phosphor along the motion trajectory. The position, trajectory, and contour profile of a moving object can be visualized in high resolution, demonstrating applications in sensing.

Excellent triboelectric and mechanical properties are achieved on the same material for the first time by developing an effective, general, straightforward, and area‐scalable approach to surface modification of a polyethylene terephthalate (PET) film via inductive‐coupled plasma etching. The modification enables gigantic enhancement of triboelectric charge density on the PET surface. Based on the modified PET as a contact material, a triboelectric nanogenerator (TENG) exhibits significantly promoted electric output compared to the one without the modification. The obtained electric output is even superior to a TENG made of conventional polytetrafluoroethylene that is known for its strongest ability of being charged by triboelectrification among all engineering plastics. Detailed characterizations reveal that the enhancement of triboelectric charge density on the PET is attributed to both chemical modification of fluorination and physical modification of roughened morphology in nanoscale. Therefore, this work proposes a new route to obtaining high‐performance TENGs by manipulating and modifying surface properties of materials.

Harvesting water wave energy presents a significantly practical route to energy supply for self-powered wireless sensing networks. Here we report a networked integrated triboelectric nanogenerator (NI-TENG) as a highly adaptive means of harvesting energy from interfacing interactions with various types of water waves. Having an arrayed networking structure, the NI-TENG can accommodate diverse water wave motions and generate stable electric output regardless of how random the water wave is. Nanoscaled surface morphology consisting of dense nanowire arrays is the key for obtaining high electric output. A NI-TENG having an area of 100 × 70 mm can produce a stable short-circuit current of 13.5 μA and corresponding electric power of 1.03 mW at a water wave height of 12 cm. This merit promises practical applications of the NI-TENG in real circumstances, where water waves are highly variable and unpredictable. After energy storage, the generated electric energy can drive wireless sensing by autonomously transmitting data at a period less than 1 min. This work proposes a viable solution for powering individual standalone nodes in a wireless sensor network. Potential applications include but are not limited to long-term environment monitoring, marine surveillance, and off-shore navigation.

A stretchable porous nanocomposite (PNC) is reported based on a hybrid of a multiwalled carbon nanotubes network and a poly(dimethylsiloxane) matrix for harvesting energy from mechanical interactions. The deformation-enabled energy-generating process makes the PNC applicable to various mechanical interactions, including pressing, stretching, bending, and twisting. It can be potentially used as an energy solution for wearable electronics.

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A biocide‐free antifouling method on wetted insulating surfaces, enabled by the oscillation of electric potential generated by an integrated triboelectric wave harvester (I‐TEWH) is reported. Distinct from previous studies that reported antifouling on conducting surfaces by applying an additional power source, this method achieves antifouling on insulating surfaces with zero‐power consumption. The electric potential in the vicinity of a protected surface oscillates in large amplitude as a result of periodically accumulated free electrons on an underlying electrode. The dynamic flow of the free electrons is driven by the I‐TEWH that converts ambient wave energy by solid–liquid interface triboelectrification. As a consequence, the oscillating electric potential disturbs the inherent charge distribution on microbes due to electrostatic induction, preventing their initial adhesion onto the protected surface and thus prohibiting the subsequent formation of macroorganisms. Significant anti‐adhesion efficiencies of as high as 99.3%, 99.1%, and 96.0% are achieved for negative‐gram bacteria (Escherichia coli), positive‐gram bacteria (Staphylococcus aureus), and diatoms (bacillariophyceze), respectively, on a smooth surface. The antifouling efficiency on a roughened surface with micro/nanostructures can be further enhanced by another 75%. This approach can be potentially utilized in coastal constructions, offshore facilities, and vessels that are either moving or stationary in port.

Extremely soft and thin electrodes with high skin conformability have potential applications in wearable devices for personal healthcare. Here, a submicrometer thick, highly robust, and conformable nanonetwork epidermal electrode (NEE) is reported. Electrospinning of polyamide nanofibers and electrospraying of silver nanowires are simultaneously performed to form a homogeneously convoluted network in a nonwoven way. For a 125 nm thick NEE, a low sheet resistance of ≈4 Ω sq−1 with an optical transmittance of ≈82% is achieved. Due to the nanofiber‐based scaffold that undertakes most of the stress during deformation, the electric resistance of the NEE shows very little variation; less than 1.2% after 50 000 bending cycles. The NEE can form a fully conformal contact to human skin without additional adhesives, and the NEE shows a contact impedance that is over 50% lower than what is found in commercial gel electrodes. Due to conformal contact even under deformation, the NEE proves to be a stable, robust, and comfortable approach for measuring electrocardiogram signals, especially when a subject is in motion. These features make the NEE promising for use in the ambulatory measurement of physiological signals for healthcare applications.