Doping a metal-organic framework material (ZIF-8) on a perovskite photoconductive detector for improving stability and photoresponsivity

Crystal engineering based on the additive passivation of defects in perovskite crystals is vital for improving crystal quality and tuning the optoelectronic properties of perovskites. Doping metal-organic framework materials (MOFs) into halide perovskites is one of the emerging methods to improve the optoelectronic properties of perovskites. Herein, a simple and effective method to dope metal-organic framework nanoparticles into organic-inorganic halide perovskite MAPbI3 films is proposed. Zeolite imidazole framework-8 (ZIF-8) nanoparticles can be uniformly dispersed in MAPbI3 perovskite films. ZIF-8 nanoparticles can effectively passivate the defects in the MAPbI3 perovskite layer, and the crystalline quality of the perovskite films is improved after doping with ZIF-8. Meanwhile, planar conductive photodetectors and photodetector arrays were prepared with perovskite films. A two-fold increase was observed in the photocurrent and photoresponsivity of photodetectors doped with ZIF-8, and the detectivity reached 8.01 x 1011 Jones. The photodetectors maintained long-term operation and environmental stability and could run at 1.2 V bias for 230 s without attenuation, retaining 90% of the initial photoresponsivity after being stored at 30-35 degrees C (R.H. 40%) for 14 days. In addition, we prepared perovskite photodetector arrays. The prepared 10 x 10 photodetector array realizes the detection and signal transmission of image information. We proposed a new method to achieve efficient mixing of MAPbI3 and ZIF-8 nanoparticles that does not require heating treatment, solvent treatment, or a vacuum process. On this basis, a 10 x 10 array of planar photoconductive detectors was prepared.