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Energy crisis and worsening greenhouse effects cause unprecedented global environmental and economic‐sustainability challenges. The emerging all‐season thermal regulation technology that can provide comfort to humans without consuming external‐energy demonstrates promising prospects. Inspired by the temperature‐accommodative skin of the color‐changing rain‐frog, a biodegradable nature‐skin‐derived thermochromic membrane (PCTM‐H) is nano‐engineered for active all‐season thermal management using the integrative interfacially wet‐casting film‐forming and spraying strategy of nature‐skin to incorporate polyvinyl alcohol and thermochromic microcapsules. Its outstanding thermochromic origins allow it to switch adaptively between cooling and heating modes without additional energy input. PCTM‐H has a light color with high reflectivity in hot summer and a dark‐color that absorbs solar radiation in cold winter, with an overall visible light modulation of ≈53.5%, solar modulation of ≈32.2%, and a remarkable emissivity in mid‐infrared band (≈86.7%). PCTM‐H has exceptional adaptive thermal management capabilities for multitudinous outdoor‐applications. Simulation results show that PCTM‐H has prominent energy‐saving efficiency in cities with different climate zones when utilized as roof‐protection membranes. Additionally, the distinguished mechanical features, weatherability, and bio‐degradability of PCTM‐H substantially increase its potential applications. This study provides a reference for the development of active all‐season thermal management materials and high‐value utilization of nature‐skin, contributing to the goal of carbon‐neutrality. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) are recognized for energy conversion efficiency and applications including electronics and energy storage devices. This study introduces a groundbreaking development in TENG by incorporating negative Poisson's ratio metamaterials to fabricate auxetic‐assisted triboelectric nanogenerators (Auxetic‐TENG), subversively overcoming the low power density of traditional materials. Subtly, an integrated layer‐by‐layer‐assembly and core–shell accumulation strategy is employed to create a synclastic polytetrafluoroethylene negative friction shell‐skeleton, into which positive Poisson's ratio nature collagen aggregate (CA) foam is inwardly embedded as the positive friction core‐material. Surprisingly, the on‐demand introduction of metamaterials in synergy with CA significantly increases the contact area and mechanical energy absorption of the Auxetic‐TENG under pressure. This enhancement in the conversion efficiency of mechanical to electricity capitalizes on the contraction origins of negative Poisson's ratio metamaterials, integrated with the expansion characteristics of the positive Poisson's ratio materials within the structure, facilitating the synergistic compression of the positive and negative friction stratum. Consequently, Auxetic‐TENG achieves an open‐circuit voltage of 85 V, an overturning four times compared to conventional contact–separation TENG, and a power density of 4.2 W m−2. Application experiments demonstrate the superior performance of auxetic‐TENG under various compression ratios and stress conditions, highlighting its potential for real‐time monitoring in healthcare applications. [ABSTRACT FROM AUTHOR]

Implantable bioelectronic devices (IBDs) have gained attention for their capacity to conformably detect physiological and pathological signals and further provide internal therapy. However, traditional power sources integrated into these IBDs possess intricate limitations such as bulkiness, rigidity, and biotoxicity. Recently, artificial "tissue batteries" (ATBs) have diffusely developed as artificial power sources for IBDs manufacturing, enabling comprehensive biological‐activity monitoring, diagnosis, and therapy. ATBs are on‐demand and designed to accommodate the soft and confining curved placement space of organisms, minimizing interface discrepancies, and providing ample power for clinical applications. This review presents the near‐term advancements in ATBs, with a focus on their miniaturization, flexibility, biodegradability, and power density. Furthermore, it delves into material‐screening, structural‐design, and energy density across three distinct categories of TBs, distinguished by power supply strategies. These types encompass innovative energy storage devices (chemical batteries and supercapacitors), power conversion devices that harness power from human‐body (biofuel cells, thermoelectric nanogenerators, bio‐potential devices, piezoelectric harvesters, and triboelectric devices), and energy transfer devices that receive and utilize external energy (radiofrequency‐ultrasound energy harvesters, ultrasound‐induced energy harvesters, and photovoltaic devices). Ultimately, future challenges and prospects emphasize ATBs with the indispensability of bio‐safety, flexibility, and high‐volume energy density as crucial components in long‐term implantable bioelectronic devices. [ABSTRACT FROM AUTHOR]

Electronic skins (e‐skins), which are mechanically compliant with human skin, are regarded as ideal electronic devices for noninvasive human–machine interaction and wearable devices. In order to fully mimic human skin, e‐skins should possess reliable mechanical properties and be able to resist external environmental factors like heat, cold, desiccation, and bacteria, while perceiving multiple external stimuli, such as temperature, humidity, and strain. Here, a transparent, mechanically robust, environmentally stable, versatile natural skin‐derived organohydrogel (NSD‐Gel) is nanoengineered through the integration of betaine, silver nanoparticles, and sodium chloride in a glycerol/water binary solvent. The transparent NSD‐Gel e‐skin exhibits outstanding tensile strength (7.33 MPa), puncture resistance, moisture retention, self‐regeneration, and antibacterial properties. Additionally, the NSD‐Gel e‐skin possesses enhanced cold/heat resistance and stimuli‐responsive characteristics that effectively sense environmental temperature and humidity changes, as well as physiological human body motion signals. In vitro and in vivo experiments show that the NSD‐Gel e‐skin confers desired biocompatibility and tissue protective properties even in extremely harsh environments (−196 °C to 100 °C). The NSD‐Gel e‐skin has great potential for applications in multidimensional wearable electronic devices, human‐machine interfaces, and artificial intelligence, generating a versatile platform for the development of high‐performance e‐skins with on‐demand properties. [ABSTRACT FROM AUTHOR]