Electronic skins, as the integration of multiple distinct sensors, have aroused broad interests owing to their great potential in sensing applications. However, problems including the interference between sensing components and the difficulty in synchronous monitoring are practically encountered when they are applied to mixed signals. In this work, efforts are devoted to trouble‐free technical strategies for laminating three sensors with different sensing abilities into a skin‐like electronic device. The use of ionic liquid, combined with particular circuit topologies, ensures the reliable stability against mechanical disturbance during the real‐time sensing tests. The intrinsic layered structure and three independent sensing functions of natural skins are successfully presented by this particular device in which three sensors with the ease of preparation are spatially integrated. The changes of temperature, pressure, and infrared light can be recorded simultaneously yet without mutual signal interference. The perfect integration of multiple functional sensors into a single skin‐like device without any signal interference makes an important progress for pursuing the goal of future electronic skins that can practically be used as skin.

For the purpose of stretchable electronics, broad interests have been paid to elastic conductors by which high tensile strain over 100% can be readily achieved. Here, a scalable-processing, dyeing-like strategy for highly stretchable polypyrrole elastomer (1450% in strain) is conceived without particular topological design. This approach effectively improves the mechanical properties of the classic insoluble polypyrrole by confined polymerization within an elastic polymer network. In terms of the easy processing, it is technically possible to prepare stretchable electronics with arbitrary shape and size for wearable electronics with low cost. The mechanism of interpenetrated networks coexisting with microphase separation is comprehensively illustrated at molecular scale. The as-fabricated polypyrrole elastomers are utilized as temperature or strain sensors for automatic fishing and region-distinct dual signal sensing. Further integration of multiple sensors offers immediate alarm for old people falling at home, which thereby proves its promising potential in practical applications.

Despite great progresses in bioprinting materials and technologies, immense challenges still remain when printing tubular tissues or organs with satisfying mechanical and chemical properties, such as blood vessel, colon, and trachea. Herein, a promising extrusion system based on an interfacial diffusion printing (IDP) technique for one-step printing of tubular tissue grafts is proposed. Specifically, this technique offers great convenience to prepare hollow hydrogel fibers with excellent mechanical properties and satisfactory biocompatibility. The tubular diameter can be readily adjusted within 6 mm, which renders the possibility of these hydrogel tubes to serve as small-diameter vascular grafts. In the model of animal trials, the hydrogel grafts with the capability of enduring arterial pressure are mechanically stable in rabbit carotid artery replacement. Because of its intrinsic simplicity and generality, the IDP technique is considered to be one of the reliable choices for more complicated bioengineering.

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Hydroxyapatite (HA), the main inorganic component of bone tissue, is mineralized with collagen fibril scaffolds during bone formation. Inspired by the process, a self-assembled porous network architecture was designed and synthesized by using the 2-ureido-4[1H]-pyrimidone (UPy) modified glycerol molecule UPy-Gly, which was further utilized as a template for biomimetic mineralization. When incubated in simulated body fluid (SBF), the HA nucleus first formed in the holes of the template by the induction of hydroxyls on the surface, grew along the nanofibers, and fused with the template to fabricate hydroxyapatite composites (UPy-Gly/HA). Transmission electron microscopic observation demonstrates that the mineral clusters are accumulated by lamella-like nano hydroxyapatite and the elasticity modulus measured by atomic force microscopy is about 5.5 GPa, which is quite close to the natural cancellous bone tissue of human both in structure and in mechanical properties. The Cell Counting Kit 8 (CCK-8) assay of UPy-Gly and UPy-Gly/HA shows noncytotoxicity to mouse fibroblast L-929 cells. This bioinspired composite will be a promising material for potential use in bone tissue implantation and regeneration engineering.

Soft electronics is an emerging field that is lending great convenience to daily life. Soft electronics have shown great potentials in health monitoring, soft robotics, the Internet of Things, and so forth. Though soft electronics based on solid conductors have been intensively investigated and some considerable progress has been achieved, the intrinsic shortcomings of solid conductors are becoming the Achilles’ heel of soft electronics. Fortunately, many of the disadvantages of solid conductors can be offset by liquid conductors. Following the attractive advantages of liquid materials, in particular high flexibility, infinite deformability, self‐healing, and ease of doping/being doped, this review article summarizes a history of soft electronics based on liquid conductors and introduces the most up‐to‐date liquid conducting materials together with their representative featured functions. Particular applications in sensors, batteries, supercapacitors, thermoelectric conversion, and even memory devices are discussed in detail to intuitively emphasize how liquid conductors benefit soft electronics. In addition, limitations of liquid conductors are also discussed, as well as the key challenges and some innovative strategies to overcome them. Finally, future perspectives are put forward to develop soft electronics that are fully composed of liquid circuits.

Solid materials for CO capture and storage have attracted enormous attention for gaseous separation, environmental protection, and climate governance. However, their preparation and recovery meet the problems of high energy and financial cost. Herein, a controllable CO capture and storage process is accomplished in an emulsion-templated polymer foam, in which CO is breathed-in under dark and breathed-out under light illumination. Such a process is likely to become a relay of natural CO capture by plants that on the contrary breathe out CO at night. Recyclable CO capture at room temperature and release under light irradiation guarantee its convenient and cost-effective regeneration in industry. Furthermore, CO mixed with CH is successfully separated through this reversible breathing in and out system, which offers great promise for CO enrichment and practical methane purification.

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