Amratisha Koth, Tuchinda Waris, Ruankham Pipat, Naikaew Atittaya, Pansa-Ngat Pimsuda, Srathongsian Ladda, Wattanathana Worawat, Shin Thant Ko Ko, Supruangnet Ratchadaporn, Nakajima Hideki, Sahasithiwat Somboon, Kanjanaboos Pongsakorn
School of Materials Science and Innovation, Faculty of Science, Mahidol University, Nakhon Pathom, 73170, Thailand.
Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand.
Sci Rep. 2022 Jun 30;12(1):11058. doi: 10.1038/s41598-022-14774-x.
Rapid advancements in perovskite materials have led to potential applications in various optoelectronic devices, such as solar cells, light-emitting diodes, and photodetectors. Due to good photoelectric properties, perovskite enables low-cost and comparable performance in terms of responsivity, detectivity, and speed to those of the silicon counterpart. In this work, we utilized triple cation perovskite, well known for its high performance, stability, and wide absorption range, which is crucial for broadband photodetector applications. To achieve improved detectivity and faster response time, graded multilayer perovskite absorbers were our focus. Sequential spray deposition, which allows stacked perovskite architecture without disturbing lower perovskite layers, was used to generate single, double, and triple-layer perovskite photodetectors with proper energy band alignment. In this work, we achieved a record on self-powered perovskite photodetector fabricated from a scalable spray process in terms of EQE and responsivity of 65.30% and 0.30 A W. The multilayer devices showed faster response speed than those of single-layer perovskite photodetectors with the champion device reaching 70 µs and 88 µs for rising and falling times. The graded band structure and the internal electric field generated from perovskite heterojunction also increase specific detectivity about one magnitude higher in comparison to the single-layer with the champion device achieving 6.82 × 10 cmHz W.
钙钛矿材料的快速发展使其在各种光电器件中具有潜在应用，如太阳能电池、发光二极管和光电探测器。由于具有良好的光电性能，钙钛矿在响应度、探测率和速度方面能够实现低成本且性能可与硅基同类器件相媲美。在这项工作中，我们使用了以高性能、稳定性和宽吸收范围而闻名的三阳离子钙钛矿，这对于宽带光电探测器应用至关重要。为了提高探测率并缩短响应时间，我们重点研究了渐变多层钙钛矿吸收体。采用顺序喷雾沉积法，该方法可以在不干扰下层钙钛矿层的情况下形成堆叠的钙钛矿结构，用于制备具有适当能带对准的单层、双层和三层钙钛矿光电探测器。在这项工作中，我们通过可扩展的喷雾工艺制备的自供电钙钛矿光电探测器在EQE和响应度方面分别达到了65.30%和0.30 A W，创下了记录。多层器件的响应速度比单层钙钛矿光电探测器更快，其中最佳器件的上升和下降时间分别达到了70 µs和88 µs。钙钛矿异质结产生的渐变能带结构和内部电场也使比探测率比单层器件提高了约一个数量级，最佳器件达到了6.82×10 cmHz W。
