Ultrathin flexible photodetectors can be conformably integrated with the human body, offering promising advancements for emerging skin-interfaced sensors. However, the susceptibility to degradation in ambient and particularly in aqueous environments hinders their practical application. Here, we report a 3.2-micrometer-thick water-resistant organic photodetector capable of reliably monitoring vital sign while submerged underwater. Embedding the organic photoactive layer in an adhesive elastomer matrix induces multidimensional hybrid phase separation, enabling high adhesiveness of the photoactive layer on both the top and bottom surfaces with maintained charge transport. This improves the water-immersion stability of the photoactive layer and ensures the robust sealing of interfaces within the device, notably suppressing fluid ingression in aqueous environments. Consequently, our fabricated ultrathin organic photodetector demonstrates stability in deionized water or cell nutrient media over extended periods, high detectivity, and resilience to cyclic mechanical deformation. We also showcase its potential for vital sign monitoring while submerged underwater.

中文翻译：

---

用于生命体征监测的防水、超薄、舒适的有机光电探测器


超薄柔性光电探测器可以与人体完美集成，为新兴的皮肤界面传感器提供了有希望的进步。然而，在环境中，特别是在水环境中对降解的敏感性阻碍了它们的实际应用。在这里，我们报告了一种 3.2 微米厚的防水有机光电探测器，能够在水下可靠地监测生命体征。将有机光敏层嵌入粘性弹性体基质中会引起多维混合相分离，从而使光敏层在顶面和底面上具有高粘附性，同时保持电荷传输。这提高了光敏层的水浸稳定性，并确保器件内界面的牢固密封，特别是抑制水环境中的液体侵入。因此，我们制造的超薄有机光电探测器在去离子水或细胞营养培养基中表现出长期稳定性、高探测率和对循环机械变形的弹性。我们还展示了它在水下监测生命体征的潜力。