Laminated Polymer-Encapsulated Halide Perovskite Photoconductors

Herein, a simple, solvent-free method to fabricate polymer-encapsulated halide perovskite photoconductors is described. Dry mechanochemical synthesis is used to prepare CsPbBr₃ in the presence of poly(butyl methacrylate) (PBMA). The resulting composite powder is then heated and pressed into a free-standing disk with a thickness controlled by a metallic spacer ring. The disk can be laminated on a glass substrate patterned with interdigitated electrodes, resulting in a planar photoconductor device. The best photoconductive performance is obtained for disks that consist of 75 wt.% CsPbBr₃ in PBMA, reaching a detectivity of ≈2 × 10¹¹ Jones. Moreover, by adjusting the thickness of the disk, narrowband detectors can be obtained due to charge collection narrowing. Depending on the thickness of the pressed disk, the position and width of the detectivity peak can be tuned. At last, the disks are tested as possible absorber materials for X-ray detectors, where ow detection limit, and fast and linear response are measured for perovskite-polymer disks with 50 wt.% perovskite content. This work shows a simple and versatile approach toward the fabrication of halide perovskite photodetectors, which can be carried out in air and without the use of solvents.