Ultrahighly Photosensitive and Highly Stretchable Rippled Structure Photodetectors Based on Perovskite Nanocrystals and Graphene

Stretchable optoelectronic devices are the need of the hour when it comes to making present day technologies user-friendly. These devices when placed conformably on the human skin or any other artificial intelligence products must function in all their capacities to get a durable and highly sensitive device performance. Stretchable photodetectors are the core fundamental constituents that fall under the umbrella of flexible optoelectronic devices. Although a significant amount of research has been reported on stretchable photodetectors, good performance still remains a challenge. Nanometer-sized methylammonium lead bromide ((MA)­PbBr₃) perovskite nanocrystals can significantly emit and absorb light in the visible spectrum. With high quantum yield and stable optical and electronic properties, when they are subjected to mechanically tunable two-dimensional (2D) composites, we obtain better performance from stretchable optoelectronic devices. Here, a hybrid photodetector composed of perovskite nanocrystals and graphene of rippled geometry is demonstrated, where a thin film of photon-absorbing perovskite nanocrystals is placed on rippled graphene that contributes to a photoresponsivity on the order of ∼6 × 10⁵ A W^–1. The large photoresponsivity value places this hybrid stretchable device in the highest position among devices with similar functionality. It is found that the photoresponsivity of the perovskite nanocrystals and graphene hybrid rippled structure photodetector is strain tunable with a stretchability up to 100%. In addition, the hybrid rippled structure photodetector has wearability and durability. All of these superior functionalities lead the way toward fabricating stretchable optoelectronic devices suitable for applications in the fields of biomedicine, defense systems, fire detection, and flexible display panels.