Solar-Blind Deep Ultraviolet Photoelectrochemical Detectors: Materials, Mechanisms, and Applications

Abstract

Photodetection technologies underpin a broad range of modern optoelectronic applications, encompassing imaging, communication, environmental monitoring, and biochemical sensing. At the core of these systems lie photodetectors, which transduce optical signals into electrical outputs, thereby defining overall device performance. Among various detection needs, solar-blind ultraviolet photodetectors (SBPDs) hold particular significance due to their intrinsic ability to suppress atmospheric background interference, enabling high-contrast detection in demanding settings such as defense and harsh environment monitoring. However, reliable UVC detection remains technologically challenging, as conventional solid-state devices often suffer from elevated dark current, intricate fabrication processes, and the necessity for external biasing. To overcome these limitations, photoelectrochemical (PEC) architectures present a compelling alternative, offering self-powered operation, structural simplicity, and improved environmental resilience. By leveraging redox reactions at the solid-liquid interface, PEC devices provide strong compatibility with ionic, aqueous, and biologically relevant environments—making them promising candidates for flexible and integrated optoelectronic systems. This review systematically summarizes recent advances in PEC SBPDs, covering fundamental principles, device configurations, and performance metrics. Particular focus is given to wide-bandgap semiconductors, including AlGaN, Ga₂O₃, and diamond. Finally, we discuss their integration into advanced functional systems and delineate existing challenges and future prospects for real-world implementation.