Band Engineering at (PEA)₂(MA)₂Pb₃I₁₀/CdS Quantum Dot Interfaces: Toward High‐Performance Photodetectors with Optimized Carrier Dynamics

Low‐dimensional organic–inorganic hybrid perovskites, known for their environmental resilience, remarkable optoelectronic properties, and layered configuration, are highly valued in the field of optoelectronics. Quantum dots (QDs) are capable of forming smooth, high‐quality, and mechanically robust films, making them ideal for use in flexible wearable devices. The perovskite‐QDs heterostructure combines the strengths of both materials, significantly enhancing device performance. It has developed an innovative method by spin‐coating (PEA) 2 (MA) 2 Pb 3 I 10 2D RP (Ruddleston‐Popper)‐phase perovskite and CdS QDs to create a Type II heterostructure. Under illumination at 405, 660, and 808 nm, the photoresponse of the PEA‐CdS QDs photodetector is up to 15 times, 12 times, and 14 times greater than that of the PEA photodetector, with the highest photoresponse reaching 0.92 A W −1 . Impressively, even after 2000 bending cycles, the photocurrent maintains 85% of its initial value. These results potentially pave the way for the development of high‐performance flexible photodetectors and suggest an advanced strategy for enhancing wearable technology.