Quasi-2D Ruddlesden-Popper Perovskites with Low Trap-States for High Performance Flexible Self-Powered Ultraviolet Photodetectors

Organic-inorganic perovskite photodetectors have drawn great attention due to their excellent performance and simple fabrication process. However, the detectivity of perovskite ultraviolet photodetectors (UV-PDs) is comparatively poor because of the high defect density in chlorine-containing 3D perovskites. Furthermore, 3D perovskites are easily degraded by high-energy ultraviolet light, limiting their practical applications. Herein, high quality quasi-2D Ruddlesden-Popper perovskite (Q-2DRPP) (PMA)(2)MA(2)Pb(3)Cl(10) (PMA(+) = C6H5CH2NH3+, MA(+) = CH3NH3+) films are prepared for UV-PDs. It is found that Q-2DRPP films have lower defect density and larger resistance than conventional 3D perovskite films, which improves the performance of UV-PDs. The dark current density and maximum detectivity of the Q-2DRPP film-based device are 4.96 x 10(-10) A cm(-2) and 2.59 x 10(12) Jones, respectively, which are both higher than those of the reference 3D perovskite-based devices (2.29 x 10(-8) A cm(-2) and 6.08 x 10(11) Jones). Moreover, Q-2DRPP film-based flexible UV-PD has excellent bending stability; its photocurrent can retain 85% of its initial value after 1000 bending cycles. Q-2DRPP film-based devices have demonstrated long-term light and environmental stability. These results imply that Q-2DRPP films have great potential for high-performance UV-PDs.

Automated summary

The performance of perovskite photodetectors was studied in this work, and it was found that devices made with quasi-2D perovskite materials performed better. Compared to conventional 3D perovskite materials, quasi-2D perovskite materials had lower defect density and higher resistance, which improved the performance of the photodetectors.