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Highlighted with bio‐degradability, paper‐based flexible pressure sensors receive significant attention in the field of wearable devices for a sustainable future. However, it remains a challenge to possess considerable sensing performance in high humidity and underwater environments, because its structure rapidly breaks down after the hydrophilic cellulose absorbs water. In this study, a facile chemical vapor deposition method is employed to conformally coat a thin hydrophobic layer onto the cellulose fibers, resulting in an encapsulating paper with high moisture tolerance. The well‐maintained porous structure reserves the superior breathability of the paper. A micro‐convex‐structured sensor layer impregnated with MXene serves as the sensing layer. As a result, an all‐paper‐based pressure sensor with high moisture tolerance and breathability is fabricated. This sensor features a broad sensing range (0–60 kPa), acceptable sensitivities (39.58 kPa−1 (0–1.01 kPa), 11.95 kPa−1 (1.01–60 kPa)), a low detection limit of ≈2.8 Pa, response and recovery time (93 and 69 ms), reliable hydrophobic breathability, and excellent repeatability (10 000 cycles). Moreover, this sensor can be safely worn on human skin and can monitor physiological signals in real‐time in different environments (including air, humid environments, and even underwater), providing a reliable, economical, and environmentally friendly solution for wearable technology. [ABSTRACT FROM AUTHOR]

Electronic skins (E‐skins) capable of biomechanical/bioelectrical signal acquisition are intensively pursued for human‐centered healthcare of daily life. For practical use, it is highly desired, yet challenging, to mass‐produce E‐skins that are soft and breathable for wearing comfort, skin‐adhesive for robust signal acquisition, multi‐signal sensing for enhanced healthcare data. Herein, a scalable fabrication strategy for a bioinspired E‐skin (SPRABE‐skin) with a multi‐layered architecture is reported that integrates skin‐like softness, self‐protection, self‐adhesion, breathability, and bimodal sensing in a single patch. The fibrous thermoplastic polyurethane (TPU) scaffold endows the SPRABE‐skin with tissue‐like softness (Young's modulus of 3.36 MPa) and stretchability, good permeability to water vapor, and self‐protection against adverse loading events. A strain sensing layer composed of MXene‐carbon nanotubes@TPU (MXene‐CNT@TPU) composition exhibits ultra‐high sensitivity in a wide sensing range (gauge factor at strain of 485% reaches 63 494). An electrode layer made of MXene‐waterborne polyurethane (MXene‐WPU) provides a highly adhesive electrode‐skin interface, which enables the acquisition of biopotentials, such as electrocardiograph (ECG), electromyograph (EMG), electroencephalo‐graph (EEG), with improved fidelity even under various dynamic interferences. Finally, a SPRABE‐skin based human‐centered healthcare system is demonstrated that realizes the wireless, long‐duration, and dynamic monitoring of ECG and running activities. [ABSTRACT FROM AUTHOR]

Nanofiber‐based electronic devices have attracted considerable interest owing to their conformal integration on complicated surfaces, flexibility, and sweat permeability. However, building complicated electronics on nanomesh structure has not been successful because of their inferior mechanical properties and processability. This limits their practical application. To achieve system‐level device applications, organic field‐effect transistors are one of the key components to be integrated with various sensors. Herein, a successful method for fabricating a biocompatible, ultrathin (≈1.5 µm), lightweight (1.85 g m–2), and mechanically durable all‐nanofiber‐based organic transistor is reported that can be in conformal contact with curved skin. Furthermore, it is the first development with a substrate‐less nanomesh organic field effect transistor. The devices exhibit satisfactory electrical performance, including an on/off value of 3.02 × 104 ± 0.9 × 104, saturation mobility of 0.05 ± 0.02 cm2 V− 1 s− 1, subthreshold slope of 1.7 ± 0.2 V dec–1, and threshold voltage of −6 ± 0.5 V. The mechanism of crack initiation is analyzed, via simulation, to understand the deformation of the nanomesh transistors. Furthermore, active matrix integrated tactile sensors entirely on the nanomeshes is successfully demonstrated, indicating their potential applicability in the field of biomedical electronics. [ABSTRACT FROM AUTHOR]

Skin‐integrated soft electronics have attracted extensive research attention due to their potential utility for fitness monitoring, disease management, human–machine interfaces, and other applications. Although many materials and device components are explored for the construction of skin‐integrated systems, achieving multifunctional sensor platform combined with good breathability and conformability on the skin remains difficult. This challenge is partly due to the processing incompatibility between planar‐fabricated microelectronics and biocompatible porous substrates. Here, a fabrication strategy that can overcome this limitation, leading to large‐area multifunctional skin electronics with breathability and conformability required for wearable applications, is reported. In this scheme, a hybrid integration of high‐performance microfabricated sensors and nanofibrous soft substrates is made possible with stamp‐based transferring techniques combined with electrospinning. The resulting membrane devices exhibit tissue‐like mechanical properties with high permeability for vapor transport. In addition, kirigami structures can be introduced into these membranes, providing high stretchability and 3D conformability for large‐area integration on the skin. The multifunctional sensors array allow for spatiotemporal measurement of bioelectrical signals, temperature, skin hydration, and potentially many other physiological parameters. The robust performance and manufacturing scalability provided by these multifunctional skin electronics may create further opportunities for the development of advanced wearable systems. [ABSTRACT FROM AUTHOR]

Wearable tensile strain sensors have aroused substantial attention on account of their exciting applications in rebuilding tactile inputs of human and intelligent robots. Conventional such devices, however, face the dilemma of both sensitive response to pressure and bending stimulations, and poor breathability for wearing comfort. In this paper, a breathable, pressure and bending insensitive strain sensor is reported, which presents fascinating properties including high sensitivity and remarkable linearity (gauge factor of 49.5 in strain 0–100%, R2 = 99.5%), wide sensing range (up to 200%), as well as superior permeability to moisture, air, and water vapor. On the other hand, it exhibits negligible response to wide‐range pressure (0–100 kPa) and bending (0–75%) inputs. This work provides a new route for achieving wearing comfortable, high‐performance, and anti‐jamming strain sensors. [ABSTRACT FROM AUTHOR]

Wearable, flexible, and even stretchable tactile sensors, such as various types of electronic skin, have attracted extensive attention, which can adapt to complex and irregular surfaces, maximize the matching of wearable devices, and conformally apply onto human organs. However, it is a great challenge to simultaneously achieve breathability, permeability, and comfortability for their development. Herein, mitigating the problem by miniaturizing and integrating the sensors is tried. Highly flexible and stretchable coaxial structure fiber‐shaped triboelectric nanogenerators (F‐TENGs) with a diameter of 0.63 mm are created by orderly depositing conductive material of silver nanowires/carbon nanotubes and encapsulated polydimethylsiloxane onto the stretchable spandex fiber. As a self‐powered multifunctional sensor, the resulting composite fiber can convert mechanical stimuli into electrical signals without affecting the normal human body. Moreover, the F‐TENGs can be easily integrated into traditional textiles to form tactile sensor arrays. Through the tactile sensor arrays, the real‐time tactile trajectory and pressure distribution can be precisely mapped. This work may provide a new method to fabricate fiber‐based pressure sensors with high sensitivity and stretchability, which have great application prospects in personal healthcare monitoring and human–machine interactions. [ABSTRACT FROM AUTHOR]

Advanced medical dressings need to meet these requirements of breathability, moisture absorption balance, antibacterial activity, and mechanical strength. Both breathability and moisture absorption balance strongly depend on the porous structure that inversely sacrifice their mechanical properties and bulk antibacterial activity. Herein, multifunctional porous structure is designed that can synchronously realize excellent antibacterial activity, breathability, superhydrophilicity, and enhanced mechanical properties just using nanofluids templating. The pore sizes, density, and functionality of porous polymers are regulated through nanofluids loading and multiple functional components including inorganic nanoparticles core and organic corona/canopy composed of organic long chains with different charges. An ionically tethered, nonylphenol polyoxyethylene ether sulfate as a canopy of nanofluids can be removed with sodium chloride solution to form porous structure, greatly improving the breathability of membrane and achieving superhydrophilicity to obtain moisture absorption balance. Meantime, exposed polysiloxane quaternary ammonium salts as covalently bonded corona of nanofluids exhibit excellent antibacterial activity. Finally, nanoparticles core endows supreme tensile strength ratio (115%) of porous membrane. Overall, nanofluids templating approach is expected to develop into a universal strategy to construct a series of multifunctional porous polymer materials via varying the component of nanofluids, which provide a promising application in biomedicine, human health, and life science. [ABSTRACT FROM AUTHOR]