Copper Sulfide Based Self-Powered Photoelectrochemical Detectors for Optical Communication in Seawater

Abstract

Underwater optical communication (UOC)is a vital component of the 6G network architecture. Photoelectrochemical (PEC) detectors have garnered extensive attention due to their simple fabrication, low cost, and self-powered operation. In this study, a CuS thin film was synthesized via a one-step electrochemical deposition method. Characterization techniquessuch as scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) confirmed the high quality of the as-prepared film. Cyclic voltammetry (CV), Mott-Schottky (M-S), and electrochemical impedance spectroscopy (EIS) measurements were performed, and the reaction mechanism was analyzed. Performance tests demonstrated that the detector exhibits favorable self-powered photoresponse at 420 nm, with a responsivity of 2.73 mA/W and a specific detectivity of 2.15×109 Jones. This work represents the first application of such a detector in a UOC system in seawater, successfully achieving the transmission of character signals.