Accurate, real-time, and noninvasive monitoring of health signals, such as heart rate, is indispensable for mobile health care. A highly sensitive and flexible photoelectric detector is the key component for collection of biological signals. Herein, a Sb₂Se₃-based photodiode is fabricated on a flexible polyimide substrate. The device exhibited impressive detection performance with 95 dB linear dynamic range, 83% external quantum efficiency, 0.42 A W^–1 photoresponsivity, less than 10^–14 A Hz^–1/2 noise current, and 500 kHz −3 dB bandwidth. Moreover, thanks to the 1D crystal structure of Sb₂Se₃, our devices demonstrate ultrahigh flexibility with negligible performance degradation after bending at 69° for a 1000× cycle. Owing to these decent features, the flexible Sb₂Se₃ photodiodes are employed for additional light-source-free heart rate detection. This work opens up an avenue toward wearable Sb₂Se₃-based photoelectric devices, such as flexible solar cells.

中文翻译：

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一维Sb ₂ Se ₃使高柔性光电二极管实现无光源心率检测

准确，实时，无创地监测健康信号（例如心率）对于移动医疗来说是必不可少的。高灵敏度和灵活的光电探测器是收集生物信号的关键组件。在此，在柔性聚酰亚胺基板上制造基于Sb ₂ Se ₃的光电二极管。该器件具有令人印象深刻的检测性能，具有95 dB的线性动态范围，83％的外部量子效率，0.42 AW ^–1的光响应性，小于10 ^–14 A Hz ^–1/2的噪声电流以及500 kHz -3 dB的带宽。此外，由于Sb ₂ Se ₃的一维晶体结构，我们的设备表现出超高的灵活性，在69°弯曲1000x周期后，性能可忽略不计。由于具有这些体面的功能，因此可采用灵活的Sb ₂ Se ₃光电二极管进行额外的无光源心率检测。这项工作为可穿戴式基于Sb ₂ Se ₃的光电器件（例如柔性太阳能电池）开辟了道路。