<b>Gas-liquid two-phase bubble flow spinning for hydrovoltaic flexible electronics</b>

通过吸收或转移游离水而不发生化学反应来发电的水力发电技术已被探索为可再生能源的潜在候选者^1-3。包括水力光伏光纤在内的自供电柔性传感器正在成为可再生能源领域的重要研究方向。然而，由于需要调节水的运动以实现性能差异 4-6，因此在功能性纤维中集成传感和发电仍然具有挑战性^4–6。在这里，我们提出了一种气液两相流纺丝方法，该方法的灵感来自蜘蛛多峰纺丝，该方法使用气泡触发的纺丝液体变形来制造空心、实心纺锤体和棘轮齿形纤维。这些结构改变了水的吸附和转移行为，使其适用于能源和传感领域的水力光伏器件的目标应用。由藻酸盐桥式 MoS₂ 制备的成型纤维可实现广泛的水力光伏应用。空心主轴光纤，在室外 2.1 V 的开路电压下发电超过 43 小时。齿形纤维表现出高灵敏度 （5.8 mV/RH%） 和快速响应时间 （0.66 s），因此开发用于鼻周期监测、诊断和治疗的智能口罩是潜在的应用。纺丝材料扩展到羧甲基纤维素、聚乙烯醇等材料，激发了结构响应式水电材料的设计并推动了纺织电子学的发展。

Hydrovoltaic technology, which generates electricity by absorbing or transferring free water without chemical reactions, has been explored as a potential candidate for renewable energy sources^1-3. Self-powered flexible sensors, including hydrovoltaic optical fibers, are emerging as important research directions in the renewable energy field. However, integrating sensing and power generation in functional fibers remains challenging due to the need to regulate water movement to achieve performance variations^4–6. Here, we propose a gas-liquid two-phase flow spinning method inspired by spider multi-peaked spinning, which uses bubble-triggered spinning liquid deformation to fabricate hollow, solid spindle, and ratchet-tooth-shaped fibers. These structures alter the water adsorption and transfer behaviors, making them suitable for targeted applications in hydrovoltaic devices in the energy and sensing fields. Shaped fibers prepared from alginate-bridged MoS₂ enable a wide range of hydrovoltaic applications. Hollow spindle fibers generate electricity for over 43 hours at an open-circuit voltage of 2.1 V outdoors. Tooth-shaped fibers exhibit high sensitivity (5.8 mV/RH%) and fast response time (0.66 s), thus potential applications include developing smart masks for nasal cycle monitoring, diagnosis, and treatment. Spinning materials are extended to carboxymethyl cellulose, polyvinyl alcohol, and other materials, inspiring the design of structure-responsive hydrovoltaic materials and promoting the development of textile electronics.