Enhancing Photodetector Performance via Interlayer Energy Transfer in 2D Hybrid Perovskite Heterostructures

Abstract Two-dimensional (2D) organic-inorganic hybrid perovskites (OIHPs) have emerged as promising materials for optoelectronic devices due to their exceptional properties. However, their application is often hindered by limited charge transfer (CT) capabilities, attributed to the insulating organic spacer layers. In this study, we address this challenge by introducing a BA 2 MA 2 Pb 3 I 10 /PEA 2 MA 2 Pb 3 I 10 heterostructure, which leverages interlayer energy transfer (ET) to overcome CT limitations. This ET mechanism leads to a substantial enhancement in photoluminescence (PL) emission, with the heterostructure displaying a ~2.4-fold increase in PL intensity compared to pristine PEA 2 MA 2 Pb 3 I 10 . Additionally, encapsulating the heterostructure boosts PL emission by 5.2 times. The impact of ET on device performance was further demonstrated in photodetectors based on this heterostructure. These devices exhibited significant improvements in photoresponse, achieving a maximum responsivity of 10 A/W, which are almost 10 times greater than those of devices fabricated from the individual BA 2 MA 2 Pb 3 I 10 and PEA 2 MA 2 Pb 3 I 10 devices. Additionally, the heterostructure device demonstrates rapid response times, with a rise time of 7 ms and a decay time of 4 ms, significantly outperforming both the pure BA 2 MA 2 Pb 3 I 10 device (450 ms rise, 470 ms decay) and thePEA 2 MA 2 Pb 3 I 10 device (350 ms rise, 370 ms decay). These findings highlight ET as an effective strategy for enhancing the optoelectronic performance of 2D OIHP-based devices, paving the way for high-efficiency applications in future photodetectors and other optoelectronic technologies.