Wang Qian, Bai Dongliang, Jin Zhiwen, Liu Shengzhong Frank
Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science & Engineering, Shaanxi Normal University Xi'an 710119 P. R. China
Dalian National Laboratory for Clean Energy, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences Dalian 116023 P. R. China
RSC Adv. 2018 Apr 19;8(27):14848-14853. doi: 10.1039/c8ra02709a. eCollection 2018 Apr 18.
Herein, ultrathin (∼35 μm) CHNHPbI (MAPbI) single-crystalline wafers have been successfully prepared by using an appropriate geometry-regulated dynamic-flow reaction system. The measurement results proved that the obtained wafers have high crystallinity, and showed broad light absorption from ultraviolet to near infrared (850 nm) which can be attributed to the indirect bandgap. Straight after, such an MAPbI wafer was used to fabricate high-quality photodetectors (PDs). On account of its faster carrier transport and significantly reduced defect density, the device exhibits a high photoresponse () of 5 A/W and short on/off response (0.039 s/0.017 s). Interestingly, by introducing a Cr interlayer between the MAPbI wafer and the Au electrode to avoid the migration of Au, the PD shows nearly no degradation when it works at 200 °C. Furthermore, the device performance shows very little degradation over the course of 60 days of storage under ambient conditions owing to its lack of grain boundaries. We believe the strategy reported here is very promising for achieving broad photodetection in a harsh environment.
在此，通过使用适当的几何形状调节动态流动反应系统，成功制备了超薄（约35μm）的CHNHPbI（MAPbI）单晶片。测量结果证明，所获得的晶片具有高结晶度，并显示出从紫外到近红外（850nm）的宽光吸收，这可归因于间接带隙。紧接着，这样的MAPbI晶片被用于制造高质量的光电探测器（PDs）。由于其更快的载流子传输和显著降低的缺陷密度，该器件表现出5A/W的高光响应率以及短的开/关响应时间（0.039s/0.017s）。有趣的是，通过在MAPbI晶片和金电极之间引入Cr中间层以避免金的迁移，该PD在200°C工作时几乎没有降解。此外，由于其没有晶界，该器件在环境条件下储存60天的过程中性能几乎没有下降。我们相信，这里报道的策略对于在恶劣环境中实现宽光谱光电探测非常有前景。
