Solar‐driven interfacial evaporation is an emerging technology with a strong potential for applications in water distillation and desalination. However, the high‐cost, complex fabrication, leaching, and disposal of synthetic materials remain the major roadblocks toward large‐scale applications. Herein, the benefits offered by renewable bacterial cellulose (BC) are considered and an all‐cellulose‐based interfacial steam generator is developed. In this monolithic design, three BC‐based aerogels are fabricated and integrated to endow the 3D steam generator with well‐defined hybrid structures and several self‐contained properties of lightweight, efficient evaporation, and good durability. Under 1 sun, the interfacial steam generator delivers high water evaporation rates of 1.82 and 4.32 kg m−2 h−1 under calm and light air conditions, respectively. These results are among the best‐performing interfacial steam generators, and surpass a majority of devices constructed from cellulose and other biopolymers. Importantly, the first example of integrating solar‐driven interfacial evaporation with water wave detection is also demonstrated by introducing a self‐powered triboelectric nanogenerator (TENG). This work highlights the potential of developing biopolymer‐based, eco‐friendly, and durable steam generators, not merely scaling up sustainable clean water production, but also discovering new functions for detecting wave parameters of surface water.

Solar‐driven interfacial evaporation has emerged as an innovative and sustainable technology for efficient, clean water production. Real‐world applications depend on new classes of low‐cost, lightweight, and robust materials that can be integrated into one monolithic device, which withstands a variety of realistic conditions on open water. Self‐repairing building blocks are highly desired to prevent permanent failures, recover original functions and maintain the lifetime of interfacial steam generators, although related studies are scarce to date. For the first time, a monolithic, durable, and self‐floating interfacial steam generator with well‐defined structures is demonstrated by integrating self‐healing hydrogels through facile processes in surface modulation and device fabrication. High and stable water evaporation rates over 2.0 kg m−2 h−1 are attained under 1 sun on both fresh water and brine with a broad range of salinity (36–210 g kg−1). The solar evaporation and desalination performance are among the best‐performing interfacial steam generators and surpass a majority of devices that are constructed by composite polymers as structural components. This study provides a perspective and highlights the future opportunities in self‐healing and damage‐tolerant materials that can simultaneously improve the performance, durability, and lifetime of interfacial steam generators in real‐world applications.

Hydrogel-based wearable sensors have experienced an explosive development, whereas functional integration to mimic the multisignal responsiveness of skin especially for pressure and temperature remained a challenge. Herein, a functional ionic hydrogel-base flexible sensor was successfully prepared by integrating the thermal-sensitive N-isopropylacrylamide (NIPAAm) into another conductive double-network hydrogel based on polyvinyl alcohol–graphene oxide (PVA–GO) and polyacrylic acid–Fe3+ (PAA–Fe3+). Because of the multisynergistic network design, the triple-network hydrogel was endowed with excellent conductivity (∼170 Ω/mm), mechanical tolerance (1.1 MPa), and rapid recoverability (within 0.5 s), which demonstrated the potential use in pressure monitoring. Moreover, the introduction of a thermal-sensitive network allowed it to capture the changes in the human body temperature accurately simultaneously and to be further developed as a flexible temperature sensor. In particular, the unsynchronization of pressure and temperature strain (straining to stability within 0.5 s and more than 50 s, respectively) caused the two electrical signals to be automatically separated. Intuitive reading of data without involving complex parameter separation calculations allowed the hydrogel to be developed as an integrated dual temperature–pressure-sensitive flexible sensor. In addition, all above properties demonstrated that the as-prepared functional hydrogel could be extended to the practical application in human–machine interactions and personalized multisignal monitoring.

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Solar-driven interfacial evaporation has emerged as an innovative and sustainable technology for clean water production. Development of hybrid systems based on monolithic designs has been of particular interest for solar...