Abstract: Harvesting energy from the environment has been regarded as a versatile strategy to satisfy increased electric energy demands in widespread applications like Internet of Things (IoT), wearable systems, electronics, energy-related devices, etc. In recent years, many viable energy harvesting technologies have flourished, such as thermoelectric, photovoltaic, photothermal, piezoelectric, and frictional electric etc. However, the application of these devices still faces various obstacles, including high environmental dependence, complex manufacturing, and low output performance. Therefore, exploring new types of flexible energy devices with high output performance, low cost and environmental friendliness is indispensable in the current 5G era.
As a rich and renewable clean energy source on Earth, natural water (such as water flow, raindrops, water evaporation, and environmental humidity) covers over 70% of the Earth's surface. In recent years, a new energy conversion called the hydrovoltaic effect has been discovered by researchers. When nanostructured materials come into direct contact with the ubiquitous liquid water, they can generate electricity without the harmful pollutants that pollute the environment. For instance, Zhang et al. prepared a structure with a wet ion energy conversion route by selectively coating ionic hygroscopic hydrogel on the carbon black surface, which is used for the encryption and display of the humidity electronic information interface (HEII). However, how to realize stable electricity generation with higher output under deformation condition, and get rid of the fixed bulky water tank are the challenges for hydroelectric generators (HEGs) to serve as a portable power supply for flexible and wearable electronics.
Textile-based materials that have light weight, flexibility and comfort, making them suitable for manufacturing wearable electronic products. In this situation, the integration of electronic products with traditional textiles has led to the emergence of intelligent textiles or electronic textiles, which have completely changed wearable electronic products. Therefore, integrating energy harvesting with textiles or developing textile-based energy devices will provide sustainable and environmentally friendly solutions for wearable human electronics. Furthermore, textile-based hydroelectric generation materials can provide efficient absorption of water molecules and fast ion/electron transport, which has great potential in the unique design of self-powered flexible HEG devices.
This article has herein propounded an efficient, flexible, and scalable HEG via using 1T phase tungsten disulfide/carbonized silk conductive fabric (1T-WS2/CS) to confront the above challenges. The single HEG of a size of only about 4 cm×1 cm can generate an output voltage of 0.45 V, an output current of 3.4 μA under an ambient condition (21 °C, 23% RH). Moreover, the integration of flexible HEG into medical masks for human respiratory monitoring has shown great potential in the field of intelligent wearables.

Key words: textile-based materials, 1T-WS2/CS, hydroelectric generators, hydrophilicity, human respiratory monitoring

摘要： 为了制备具有水伏发电性能的纺织品材料，采用高温碳化和水热合成的方法成功制备了1T相二硫化钨/碳化蚕丝(1T-WS2/CS)导电织物；并将两个铝电极连接在该织物两端，制备了一种水伏发电机（HEG）。利用X射线粉末衍射仪、扫描电子显微镜和拉曼光谱仪等对1T-WS2、CS和1T-WS2/CS导电织物的微观形貌和化学结构进行了表征分析；使用接触角仪、吉利时Keithley 2400和温湿度柜等对HEG的亲水性能、输出电压和输出电流进行了测试。结果表明：1T-WS2纳米片均匀地生长在CS表面；所制备的1T-WS2/CS具有优异的亲水性，水接触角从19°减小到0°仅需2 s；在20 μL去离子水作用下，尺寸为4 cm×1 cm的HEG可以产生高达0.45 V的输出电压和3.40 μA的输出电流。此外，HEG可以集成到医用口罩上用于人体健康呼吸监测，为未来可穿戴自供电设备的设计提供了参考。

关键词: 纺织品材料, 1T相二硫化钨/碳化蚕丝导电织物, 水伏发电机, 亲水性, 人体健康呼吸监测