As an emerging 2D layered material, Bi₂O₂Se has shown great potential for applications in thermoelectric and electronics, due to its high carrier mobility, near‐ideal subthreshold swing, and high air‐stability. Although Bi₂O₂Se has a suitable band gap for infrared (IR) applications, its photoresponse properties have not been investigated. Here, high‐quality ultrathin Bi₂O₂Se sheets are synthesized via a low‐pressure chemical vapor deposition method. The thickness of 90% Bi₂O₂Se sheets is below 10 nm and lateral sizes mainly distribute in the range of 7–11 µm. In addition, it is found that triangular sheets largely lack “O” content, even only 0.2 for Bi₂O_0.2Se. The near‐IR photodetection performance of Bi₂O₂Se nanosheets is systematically studied by variable temperature measurements. The response time, responsivity, and detectivity can approach up to 2.8 ms, 6.5 A W⁻¹, and 8.3 × 10¹¹ Jones, respectively. Additionally, the critical performance parameters, including responsivity, rising time, and decay time, remain at almost the same level when the temperature is changed from 80 to 300 K. These phenomena are likely due to the fact that as‐grown ultrathin Bi₂O₂Se sheets have no surface trap states and shallow defect energy levels. The findings indicate ultrathin Bi₂O₂Se sheets have great potentials for future applications in ultrafast, flexible near‐IR optoelectronic devices.

中文翻译：

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基于超薄Bi2O2Se纳米片的高性能近红外光电探测器

作为一种新兴的2D层状材料，Bi ₂ O ₂ Se由于具有高的载流子迁移率，接近理想的亚阈值摆幅和高的空气稳定性，在热电和电子领域具有广阔的应用前景。尽管Bi ₂ O ₂ Se具有适合红外（IR）应用的带隙，但尚未研究其光响应特性。在此，通过低压化学气相沉积法合成了高质量的超薄Bi ₂ O ₂ Se片。厚度90％Bi ₂ O ₂硒片低于10 nm，横向尺寸主要分布在7–11 µm的范围内。另外，发现三角形片材很大程度上缺乏“ O”含量，对于Bi ₂ O _0.2 Se甚至仅为0.2 。通过可变温度测量系统地研究了Bi ₂ O ₂ Se纳米片的近红外光电探测性能。响应时间，响应度和检测率可达到2.8 ms，6.5 AW ^-1和8.3×10 ¹¹琼斯分别。此外，当温度从80 K更改为300 K时，包括响应度，上升时间和衰减时间在内的关键性能参数几乎保持在同一水平。这些现象很可能是由于生长的超薄Bi ₂ O所致。₂ Se片没有表面陷阱状态且缺陷能级较浅。研究结果表明，超薄的Bi ₂ O ₂ Se片材在超快，柔性近红外光电器件中的未来应用具有巨大的潜力。