Solar-enabled evaporation for seawater desalination is an attractive, renewable, and environment-friendly technique, and tremendous progress has been achieved by developing various photothermal membranes. However, traditional photothermal membranes directly float on water, resulting in some limitations such as unavoidable heat-loss to bulk water and severe salt accumulation. To solve these problems, a hydrophilic, polymer nanorod-coated photothermal fabric is designed and fabricated, and then an indirect-contact evaporation system by hanging the fabric is demonstrated. The two ends of the fabric are designed to be in contact with seawater to guide water flow through capillary suction. Both arc-shaped top/bottom surfaces of the hanging fabrics are exposed to air, which can prevent heat dissipation to bulk seawater and facilitate the double-surface evaporation upon sunlight irradiation. Our design leads to an efficient evaporation rate of 1.94 kg m −2 h −1 and high solar efficiency of 89.9% upon irradiation with sunlight (1.0 kW m −2 ). Importantly, the highly concentrated brine can drip from the bottom of the arc-shaped fabric, without the appearance of solid-salt accumulation. This indirect-contact evaporation system establishes a new path to continuously and economically produce watersteam from seawater for fresh-water and concentrated brine for the chlor-alkali industry.

A light weight, economic, and high–energy density Zn/MnO 2 fiber battery was integrated with a textile body area network.

Solar-driven seawater evaporation is usually achieved on floating evaporators, but the performances are substantially limited by high evaporation enthalpy, solid salt crystallization, and reduced evaporation due to inclined sunlight. To solve these problems, we fabricated hierarchical polyacrylonitrile@copper sulfide (PAN@CuS) fabrics and proposed a prototype of heliotropic evaporator. Hierarchical PAN@CuS fabrics show significantly decreased water-evaporation enthalpy (1956.32 kJ kg −1 , 40 °C), compared with that of pure water (2406.17 kJ kg −1 , 40 °C), because of the disorganization of the hydrogen bonds at the CuS interfaces. Based on this fabric, a heliotropic evaporation model was developed, where seawater slowly flows from high to low in the fabric. Under solar irradiation (1.0 kW m −2 ), this model exhibits a high-rate evaporation (∼2.27 kg m −2 h −1 ) and saturated brine production without solid salt crystallization. In particular, under inclined sunlight (angle range: from −90°to +90°), the heliotropic model retains an almost unchanged solar evaporation rate, whereas the floating model shows severe evaporation reduction (83.9%). Therefore, our study provides a strategy for reducing the evaporation enthalpy, maximally utilizing solar energy and continuous salt-free desalination.

Nanostructured photothermal membranes hold great potential for solar-driven seawater desalination; however, their pragmatic applications are often limited by substantial salt accumulation. To solve this issue, we have designed and prepared flexible and washable carbon-nanotube-embedded polyacrylonitrile nonwoven fabrics by a simple electrospinning route. The wet fabric exhibits a strong photoabsorption in a wide spectral range (350–2500 nm), and it has a photoabsorption efficiency of 90.8%. When coated onto a polystyrene foam, the fabric shows a high seawater evaporation rate of 1.44 kg m–2 h–1 under simulated sunlight irradiation (1.0 kW m–2). With a high concentration of simulated seawater as the model, the accumulation of solid salts can be clearly observed on the surface of the fabric, resulting in a severe decay of the evaporation rate. These salts can be effortlessly washed away from the fabric through a plain handwashing process. The washing process has a negligible influence on the morphology, photoabsorption, and evaporation performance of the fabric, demonstrating good durability. More importantly, a larger fabric can easily be fabricated, and the combination of washable fabrics with various parallel PS foams can facilitate the construction of large-scale outdoor evaporation devices, conferring the great potential for efficient desalination of seawater under natural sunlight.

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Conventional wide bandgap semiconductors can absorb UV/visible light but have no photoabsorption band in the near-infrared (NIR) region, leading to difficulty in their use as NIR-responsive agents. With TiO as an example, we report the tuning from UV-responsive TiO nanocrystals to blue TiO nanocrystals with newly appeared NIR absorption band through the Nb-doping strategy. A strong NIR band should result from the localized surface plasmon resonances due to the considerable free electrons originating from the efficient incorporation of Nb ions (<15.5%). Interestingly, under the irradiation of a 1064 nm laser, Nb-doped TiO nanocrystals can convert laser energy into heat, and higher Nb-doping content can lead to higher NIR-induced temperature elevation, highlighting that the photothermal performances of TiO nanocrystals can be dynamically modulated by adjusting the Nb-doping levels. After coating with PEGylated phospholipid, the resulting nanocrystals display water dispersibility, high photothermal conversion efficiency and cytocompatibility. Therefore, these Nb-doped TiO nanocrystals can be used as efficient and heavy-metal-free nanoagents for the simultaneous NIR/photoacoustic imaging and photothermal therapy of tumors using a 1064 nm laser in the second biological window.

Continuously and accurately monitoring pulse‐wave signals is critical to prevent and diagnose cardiovascular diseases. However, existing wearable pulse sensors are vulnerable to motion artifacts due to the lack of proper adhesion and conformal interface with human skin during body movement. Here, a highly sensitive and conformal pressure sensor inspired by the kirigami structure is developed to measure the human pulse wave on different body artery sites under various prestressing pressure conditions and even with body movement. COMSOL multiphysical field coupling simulation and experimental testing are used to verify the unique advantages of the kirigami structure. The device shows a superior sensitivity (35.2 mV Pa−1) and remarkable stability (>84 000 cycles). Toward practical applications, a wireless cardiovascular monitoring system is developed for wirelessly transmitting the pulse signals to a mobile phone in real‐time, which successfully distinguished the pulse waveforms from different participants. The pulse waveforms measured by the kirigami inspired pressure sensor are as accurate as those provided by the commercial medical device. Given the compelling features, the sensor provides an ascendant way for wearable electronics to overcome motion artifacts when monitoring pulse signals, thus representing a solid advancement toward personalized healthcare in the era of the Internet of Things.