Viologen phosphoric acid salt modified PEDOT : PSS for high‐performance 3D perovskite photodetectors

Abstract

Abstract Perovskite photodetectors (ePDs) have shown significant promise for applications in imaging and optical communications due to their excellent optoelectronic properties. Dark current density ( J d ) plays a crucial role in determining the performance of 3D PePDs based on poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). Herein, a novel viologen derivative, 1‐allyl‐1′‐(2‐phosphonoethyl)‐viologen (APV), is introduced into PEDOT:PSS to improve the crystalline quality of the perovskite film and effectively suppress dark current. Consequently, the optimized 3D PePD achieves an ultra‐low J d of 5.75 × 10 −7 mA cm −2 at −0.5 V and a maximum specific detectivity of 2.08 × 10 13 Jones at 705 nm, positioning it among the top high‐performance 3D PePDs for visible photodetection. Furthermore, the optimized PePD exhibits a fast response time of 256 ns and a large bandwidth of 1.5 MHz. Upon successful integration into an optical wireless communication (OWC) system as the signal receiver, it demonstrates a data rate of up to 12.5 Mbps with minimal distortion. We believe that APV modification provides a universal strategy to realize sensitive PePDs, potentially revolutionizing the applications of OWC and imaging. image