Flexible pressure sensors have attracted great interest as they play an important role in various fields such as health monitoring and human–machine interactions. The design of the pressure sensors still faces challenges in achieving a high sensitivity for a wide sensing range, and the interference of water restricts the applications of the sensors. Herein, we developed a graphene–polydimethylsiloxane film combining a hierarchical surface with nanowrinkles on it and a hollow structure. The microstructure design of the composite can be facilely controlled to improve the sensing and hydrophobic performance by tailoring the microsphere building units. Attributed to the irregular surface and hollow structure of the sensing layer, the optimized sensor exhibits a superior sensitivity of 1085 kPa^–1 in a 50 kPa linear range. For practical applications, the nanowrinkles on the surface of the microspheres and the polymer coating endow the composite with waterproof properties. Inspired by the dual receptors of the skin, two designed microstructured films can simply integrate into one with double-sided microstructures. The sensing performance and the water-repellence property allow the sensor to detect physiological signals under both ambient and underwater conditions. Furthermore, underwater stimuli detection and communication are demonstrated. This method of fabricating a flexible sensor shows great potential in wearable and robotic fields.

中文翻译：

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一种用于高灵敏度和超疏水性压力传感器的新型中空石墨烯/聚二甲基硅氧烷复合材料


柔性压力传感器因其在健康监测和人机交互等各个领域发挥着重要作用而引起了人们的极大兴趣。压力传感器的设计仍然面临着在宽传感范围内实现高灵敏度的挑战，并且水的干扰限制了传感器的应用。在此，我们开发了一种石墨烯-聚二甲基硅氧烷薄膜，结合了带有纳米皱纹的分层表面和中空结构。通过定制微球结构单元，可以轻松控制复合材料的微观结构设计，以提高传感和疏水性能。由于传感层的不规则表面和中空结构，优化后的传感器在 50 kPa 线性范围内表现出 1085 kPa ^–1 的卓越灵敏度。在实际应用中，微球表面的纳米皱纹和聚合物涂层赋予复合材料防水性能。受皮肤双重感受器的启发，两种设计的微结构薄膜可以简单地整合成一种具有双面微结构的薄膜。传感性能和防水特性使传感器能够在环境和水下条件下检测生理信号。此外，还演示了水下刺激检测和通信。这种制造柔性传感器的方法在可穿戴和机器人领域显示出巨大的潜力。