Wearable mechanical sensors are susceptible to moisture, causing inaccuracy for monitoring human health and body motions. Although the superhydrophobic barrier on the sensor surface has been extensively explored as a passive water repel strategy, the dense superhydrophobic surface often has limited flexibility and inevitably degradates in high humidity or saturated water vapor environments due to the nucleation and growth of small size water molecules. This work reports a superhydrophobic MXene-sodium alginate sponge (SMSS) pressure sensor with efficient low-voltage Joule heating to provide sustained superhydrophobicity for moisture-resistant sensing. The superhydrophobic surface on the outside can repel large size water droplets, whereas the Joule heating efficiently removes small size water droplets and significantly reduces water molecule adsorption throughout the sponge. Because of the sustained superhydrophobic barrier and high porosity in the sponge, the SMSS pressure sensor with high sensitivity, large sensing range, and quick response can accurately and reliably function and monitor varying biophysical signals even in extreme use scenarios with high humidity or water vapor environments.

可穿戴机械传感器容易受潮，导致人体健康和身体运动监测不准确。尽管传感器表面的超疏水屏障作为一种被动防水策略已被广泛探索，但致密的超疏水表面通常具有有限的灵活性，并且由于小尺寸水分子的成核和生长，在高湿度或饱和水蒸气环境中不可避免地会降解。这项工作报告了一种超疏水 MXene-海藻酸钠海绵 (SMSS) 压力传感器，具有高效的低压焦耳加热功能，可为防潮传感提供持续的超疏水性。外部的超疏水表面可以排斥大尺寸的水滴，而焦耳加热可以有效去除小尺寸的水滴，并显着减少整个海绵对水分子的吸附。由于海绵中持续的超疏水屏障和高孔隙率，即使在高湿度或水蒸气环境的极端使用场景下，SMSS压力传感器也具有高灵敏度、大传感范围和快速响应的特点，能够准确可靠地工作并监测变化的生物物理信号。