High-performance ultraviolet detector based on self-assembled 3D/2D perovskite heterostructure

Heterogeneous assembly of metal halide perovskites (MHPs) structures offers convenience for promoting the interfacial properties of perovskite heterojunctions, which have been widely used in the new generation of photoelectric devices. In this study, three-dimensional (3D) CsPbBr₃ quantum dots (CPB QDs) were epitaxially grown on two-dimensional (2D) (BA)₂PbBr₄ nanoplates (BPB NPs) via self-assembly in a toluene mixing solution. The morphological, structural, and optical properties of the synthesized structure reveal that a highly-qualified interface and coherence were formed between the two different perovskites. These heterostructures (HSs) facilitate the separation and transportation of electrons and holes in opposite directions. Based on this property, a high-performance ultraviolet light detector was fabricated by depositing a layer of CPB@BPB film on a textured silicon (T-Si) substrate. The prepared CPB@BPB/T-Si detector has shown enhanced properties i.e. quick response time, high responsivity (6.9 A W^-1), high detection rate (3.17 × 10⁹ jones), and low detection limit (0.24 μW cm^-2). This enhanced performance could be attributed to the large light-absorbing area, effective carrier transport channels in BPB NPs, and improved interfacial properties of the CPB@BPB HS.