closely relevant to normal bodily functions as well as clinical cues of the progression of various diseases. Thus, their continuous and real-time acquisition with soft on-skin electronics, in a manner that does not disrupt our routine daily activities, will be useful for medical diagnostics, fitness tracking, human-machine interface, athletic training, and many others. During the past decade, soft on-skin electronics have been achieved by employing flexible and stretchable forms of inorganic electronic materials, [1][2][3] intrinsically soft organic electronic materials, [6][7][8][9] or emerging nanomaterials [10][11][12][13] as device components and using elastomers or plastics as substrates. However, one critical scientific challenge is that most materials used for on-skin electronics have limited gas permeability, which blocks sweat gland and constrains perspiration evaporation, resulting in adverse physiological and psychological effects, such as rashes, stuffiness, and/or other inflammatory skin responses, limiting their longterm feasibility. [10] In addition, the device fabrication process of on-skin electronics usually involves e-beam or photolithography, thin-film deposition, etching, and/or other complicated procedures, which are costly and time-consuming, constraining their practical applications.Great progress has been recently achieved to address the aforementioned two challenges. For example, free-standing gold nanomesh conductors were used to develop on-skin electronics with high gas permeability, which can significantly suppress the risks of skin inflammation, but are limited to complex fabrication processes such as electrospinning and vacuum deposition. [10] In another study, a "cut-and-paste" manufacturing method was developed to offer a simple way of fabricating multiparametric on-skin electronic systems. [17] However, the materials used for device fabrication, such as gold and aluminum, have limited gas permeability. Therefore, it is highly desirable to develop a simple and effective approach of making on-skin electronics using highly gas-permeable materials.Introducing porous structures into existing functional materials is a powerful way to tailor their gas permeability as well Soft on-skin electronics have broad applications in human healthcare, humanmachine interface, robotics, and others. However, most current on-skin electronic devices are made of materials with limited gas permeability, which constrain perspiration evaporation, resulting in adverse physiological and psychological effects, limiting their long-term feasibility. In addition, the device fabrication process usually involves e-beam or photolithography, thin-film deposition, etching, and/or other complicated procedures, which are costly and time-consuming, constraining their practical applications. Here, a simple, general, and effective approach for making multifunctional on-skin electronics using porous materials with high-gas permeability, consisting of laserpatterned porous graphene as the sensing components and sugar-templa...

Strategically designed, well-defined 3D architectures could offer great opportunities, that are unavailable in their 2D counterparts, for a broad spectrum of applications, such as microelectronics, bioelectronics, photonics and optoelectronics, micro-electromechanical systems, metamaterials, energy storage and harvesting, soft robotics, and many others. Existing manufacturing techniques of 3D structures mainly include 3D printing, templated growth, fluidic self-assembly, and mechanically guided 3D assembly. Among these methods, the mechanically guided 3D assembly has recently attracted broad attention in the scientific community. The process starts from the planar fabrication of patterned 2D precursor structures, followed by the 2D-to-3D shape transformation via controlled rolling, folding, curving, and/ or buckling. [4] This process is naturally compatible with existing advanced planar fabrication technologies (e.g., lithographic and laser-processing techniques). Consequently, micro/nanoscale structures, sensors and/or other functional components Mechanically guided, 3D assembly has attracted broad interests, owing to its compatibility with planar fabrication techniques and applicability to a diversity of geometries and length scales. Its further development requires the capability of on-demand reversible shape reconfigurations, desirable for many emerging applications (e.g., responsive metamaterials, soft robotics). Here, the design, fabrication, and modeling of soft electrothermal actuators based on laser-induced graphene (LIG) are reported and their applications in mechanically guided 3D assembly and human-soft actuators interaction are explored. Over 20 complex 3D architectures are fabricated, including reconfigurable structures that can reshape among three distinct geometries. Also, the structures capable of maintaining 3D shapes at room temperature without the need for any actuation are realized by fabricating LIG actuators at an elevated temperature. Finite element analysis can quantitatively capture key aspects that govern electrothermally controlled shape transformations, thereby providing a reliable tool for rapid design optimization. Furthermore, their applications are explored in human-soft actuators interaction, including elastic metamaterials with human gesture-controlled bandgap behaviors and soft robotic fingers which can measure electrocardiogram from humans in an on-demand fashion. Other demonstrations include artificial muscles, which can lift masses that are about 110 times of their weights and biomimetic frog tongues which can prey insects.

In addition to mechanical compliance, achieving the full potential of on-skin electronics needs the introduction of other features. For example, substantial progress has been achieved in creating biodegradable, self-healing, or breathable, on-skin electronics. However, the research of making on-skin electronics with passive-cooling capabilities, which can reduce energy consumption and improve user comfort, is still rare. Herein, we report the development of multifunctional on-skin electronics, which can passively cool human bodies without needing any energy consumption. This property is inherited from multiscale porous polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SEBS) supporting substrates. The multiscale pores of SEBS substrates, with characteristic sizes ranging from around 0.2 to 7 µm, can effectively backscatter sunlight to minimize heat absorption but are too small to reflect human-body midinfrared radiation to retain heat dissipation, thereby delivering around 6 °C cooling effects under a solar intensity of 840 W⋅m−2. Other desired properties, rooted in multiscale porous SEBS substrates, include high breathability and outstanding waterproofing. The proof-of-concept bioelectronic devices include electrophysiological sensors, temperature sensors, hydration sensors, pressure sensors, and electrical stimulators, which are made via spray printing of silver nanowires on multiscale porous SEBS substrates. The devices show comparable electrical performances with conventional, rigid, nonporous ones. Also, their applications in cuffless blood pressure measurement, interactive virtual reality, and human–machine interface are demonstrated. Notably, the enabled on-skin devices are dissolvable in several organic solvents and can be recycled to reduce electronic waste and manufacturing cost. Such on-skin electronics can serve as the basis for future multifunctional smart textiles with passive-cooling functionalities.

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