Electronic tattoos (E-tattoos), which can be intimately mounted on human skin for noninvasive and high-fidelity sensing, have attracted the attention of researchers in the field of wearable electronics. However, fabricating E-tattoos that are capable of self-healing and sensing multistimuli, similar to the inherent attributes of human skin, is still challenging. Herein, a healable and multifunctional E-tattoo based on a graphene/silk fibroin/Ca 2+ (Gr/SF/Ca 2+ ) combination is reported. The highly flexible E-tattoos are prepared through printing or writing using Gr/SF/Ca 2+ suspension. The graphene flakes distributed in the matrix form an electrically conductive path that is responsive to environmental changes, such as strain, humidity, and temperature variations, endowing the E-tattoo with high sensitivity to multistimuli. The performance of the E-tattoo is investigated as a strain, humidity, and temperature sensor that shows high sensitivity, a fast response, and long-term stability. The E-tattoo is remarkably healed after damage by water because of the reformation of hydrogen and coordination bonds at the fractured interface. The healing efficiency is 100% in only 0.3 s. Finally, as proof of concept, its applications for monitoring of electrocardiograms, breathing, and temperature are shown. Based on its unique properties and superior performance, the Gr/SF/Ca 2+ E-tattoo may be a promising candidate material for epidermal electronics.

Recently, electronic skin and smart textiles have attracted considerable attention. Flexible sensors, as a kind of indispensable components of flexible electronics, have been extensively studied. However, wearable airflow sensors capable of monitoring the environment airflow in real time are rarely reported. Herein, by mimicking the spider's fluff, an ultrasensitive and flexible all‐textile airflow sensor based on fabric with in situ grown carbon nanotubes (CNTs) is developed. The fabric decorated with fluffy‐like CNTs possesses exceptionally large contact area, endowing the airflow sensor with superior properties including ultralow detection limit (≈0.05 m s−1), multiangle airflow differential response (0°–90°), and fast response time (≈1.3 s). Besides, the fluffy fabric airflow sensor can be combined with a pristine fabric airflow sensor to realize highly sensitive detection in a wide airflow range (0.05–7.0 m s−1). Its potential applications including transmitting information according to Morse code by blowing the sensors, monitoring increasing and decreasing airflow velocity, and alerting blind people walking outside about potential hazard induced by nearby fast‐moving objects are demonstrated. Furthermore, the airflow sensor can be directly integrated into clothing as stylish designs without sacrificing comfortness. It is believed that the ultrasensitive all‐textile airflow sensor holds great promise for applications in smart textiles and wearable electronics.

Protective clothing plays a vital role in safety and security. Traditional protective clothing can protect the human body from physical injury. It is highly desirable to integrate modern wearable electronics into a traditional protection suit to endow it with versatile smart functions. However, it is still challenging to integrate electronics into clothing through a practical approach while keeping the intrinsic flexibility and breathability of textiles. In this work, we realized the direct writing of laser-induced graphene (LIG) on a Kevlar textile in air and demonstrated the applications of the as-prepared Janus graphene/Kevlar textile in intelligent protective clothing. The CO and N–C bonds in Kevlar were broken, and the remaining carbon atoms were reorganized into graphene, which can be ascribed to a photothermal effect induced by the laser irradiation. Proof-of-concept devices based on the prepared graphene/Kevlar textile, including flexible Zn–air batteries, electrocardiogram electrodes, and NO2 sensors, were demonstrated. Further, we fabricated self-powered and intelligent protective clothing based on the graphene/Kevlar textile. The laser-induced direct writing of graphene from commercial textiles in air conditions provides a versatile and rapid route for the fabrication of textile electronics.

The Zn metal anode is considered one of the most promising anode choices for aqueous Zn-based batteries. Nevertheless, dendrites and intricate side reactions have hindered its usage. Herein, an elastic and anti-corrosive interlayer is introduced to address the problem. The idiosyncratic dielectric behavior of amorphous and nanostructured silicon nitride (Si 3 N 4 ) is utilized to manipulate the ion kinetics, by uniformly dispersing its particles in polyacrylonitrile (PAN) to fabricate an interlayer attached to Zn metal (PSN-Zn). PAN serves as an elastic constraint to inhibit drastic dendrite evolution and blocks H 2 O/O 2 corrosion, and Si 3 N 4 with a high dielectric constant can facilitate the ion kinetics and endow uniform Zn deposition. The electrochemical stability and deposition consistency of the Zn anodes are greatly improved, with an extended lifespan of over 800 h at 1 mA cm −2 . Even under draconian deep-discharging (DOD Zn = 60%) and high current density (10 mA cm −2 ), the PSN-Zn anode can still operate stably for over 250 h. The effect of the dielectric property is systematically discussed and verified by experiments and theoretical simulations. Moreover, full cells with vanadium-and manganesebased cathodes also deliver excellent performance, indicating the use of the multifunctional interlayer as an appealing approach for rechargeable aqueous zinc batteries.

Skin, the largest organ in the human body, is sensitive to external stimuli.In recent years, an increasing number of skin-inspired electronics, including wearable electronics, implantable electronics, and electronic skin, have been developed because of their broad applications in healthcare and robotics.Physical sensors are one of the key building blocks of skin-inspired electronics. Typical physical sensors include mechanical sensors, temperature sensors, humidity sensors, electrophysiological sensors, and so on. In this review, we systematically review the latest advances of skin-inspired mechanical sensors, temperature sensors, and humidity sensors. The working mechanisms, key materials, device structures, and performance of various physical sensors are summarized and discussed in detail. Their applications in health monitoring, human disease diagnosis and treatment, and intelligent robots are reviewed. In addition, several novel properties of skin-inspired physical sensors such as versatility, self-healability, and implantability are introduced. Finally, the existing challenges and future perspectives of physical sensors for practical applications are discussed and proposed. K E Y W O R D Selectronics skin, flexible electronics, humidity sensors, mechanical sensors, temperature sensors, wearable sensors

Despite the impressive merits of low-cost and high-safety electrochemical energy storage for aqueous zinc ion batteries, researchers have long struggled against the unresolved issues of dendrite growth and the side reactions of zinc metal anodes. Herein, a new strategy of zinc-electrolyte interface charge engineering induced by amino acid additives is demonstrated for highly reversible zinc plating/stripping. Through electrostatic preferential absorption of positively charged arginine molecules on the surface of the zinc metal anode, a self-adaptive zinc-electrolyte interface is established for the inhibition of water adsorption/hydrogen evolution and the guidance of uniform zinc deposition. Consequently, an ultra-long stable cycling up to 2200 h at a high current density of 5 mA cm −2 is achieved under an areal capacity of 4 mAh cm −2 . Even cycled at an ultra-high current density of 10 mA cm −2 , 900 h-long stable cycling is still demonstrated, demonstrating the reliable self-adaptive feature of the zinc-electrolyte interface. This work provides a new perspective of interface charge engineering in realizing highly reversible bulk zinc anode that can prompt its practical application in aqueous rechargeable zinc batteries.

Aqueous zinc batteries, that demonstrate high safety and low cost, are considered promising candidates for large‐scale energy storage. However, Zn anodes suffer from rapid performance deterioration due to the severe Zn dendrite growth and side reactions. Herein, with a low‐cost ammonium acetate (NH4OAc) additive, a self‐regulated Zn/electrolyte interface is built to address these problems. The NH4+ induces a dynamic electrostatic shielding layer around the abrupt Zn protuberance to make the Zn deposition uniform, and the OAc− acts as an interfacial pH buffer to suppress the proton‐induced side reactions and the precipitation of insoluble by‐products. As a result, in the electrolyte with the NH4OAc additive, Zn anodes exhibit a long cycling stability of 3500 h at 1 mA cm−2, an impressive cumulative areal capacity of 5000 mAh cm−2 at 10 mA cm−2, and a high Coulombic efficiency of ≈99.7%. A prototype full cell coupled with a NH4V4O10 cathode performs much better in terms of capacity retention than the additive‐free case. The findings pave the way for developing practical Zn batteries.

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