Given their high photoconversion efficiency, organometal halide perovskites have attracted much interest in ultraviolet-visible-near infrared photodetectors (PDs). However, recombination of carriers in perovskites, which leads to low photocurrent, has always been an adverse factor for device performance. Here, we demonstrate a way to overcome this problem by incorporating technologically-mature Si. Meanwhile, the dark current of the device can be maintained at a low level after inserting a TiO₂ layer between the CH₃NH₃PbI₃ film and the Si substrate. The fabricated CH₃NH₃PbI₃/TiO₂/Si tri-component PD displays a high on/off ratio of 6 × 10³ and a high detectivity of 4.85 × 10¹³ Jones. In addition, the PD shows broad photoresponse with a long cut-off wavelength of 1100 nm. The design here provides an intriguing way for improving perovskite-based PDs.

中文翻译：

---

具有高开/关比和高探测灵敏度的广谱响应钙钛矿光电探测器†

鉴于其高的光电转换效率，有机金属卤化物钙钛矿对紫外可见近红外光电探测器（PD）引起了极大的兴趣。然而，钙钛矿中载流子的复合导致低光电流，一直是器件性能的不利因素。在这里，我们展示了一种通过结合技术成熟的Si来克服此问题的方法。同时，在CH ₃ NH ₃ PbI ₃膜和Si衬底之间插入TiO ₂层之后，可以将器件的暗电流保持在较低的水平。制备的CH ₃ NH ₃ PbI ₃ / TiO ₂/ Si三组分PD显示出6×10 ³的高开/关比和4.85×10 ¹³ Jones的高检测率。另外，PD显示出宽的光响应，具有1100nm的长截止波长。这里的设计为改进基于钙钛矿的PD提供了一种有趣的方法。