Recent advances in self‐powered and flexible UVC photodetectors

Abstract

Ultraviolet-C (UVC) radiation is employed in various applications, including irreplaceable applications in military and civil fields, such as missile guidance, flame detection, partial discharge detection, disinfection, and wireless communication. Although most modern electronics are based on Si, UVC detection technology remains a unique exception because the short wavelength of UV radiation makes efficient detection with Si difficult. In this review, recent challenges in obtaining ideal UVC photodetectors with various materials and various forms are introduced. An ideal photodetector must satisfy the following requirements: high sensitivity, fast response speed, high on/off photocurrent ratio, good regional selectivity, outstanding reproducibility, and superior thermal and photo stabilities. UVC detection is still in its infancy compared to the detection of UVA as well as other photon spectra, and recent research has focused on different key components, including the configuration, material, and substrate, to acquire battery-free, super-sensitive, ultra-stable, ultra-small, and portable UVC photodetectors. We introduce and discuss the strategies for fabricating self-powered UVC photodetectors on flexible substrates in terms of the structure, material, and direction of incoming radiation. We also explain the physical mechanisms of self-powered devices with various architectures. Finally, we present a brief outlook that discusses the challenges and future strategies for deep-UVC photodetectors. K E Y WO R D Sphoto-absorber, photoconductor, responsivity, UV radiation  INTRODUCTIONUltraviolet (UV) radiation is an ordinary component of solar radiation. Although it accounts for less than 10% of the total sunlight, UV radiation has a severe influence on humanity. The International Commission on Illumination (CIE) divides the spectrum of solar electromagnetic radiation into three bands, as shown in Figure 1: UVA (315-400 nm), UVB (280-315 nm), and UVC (100-280 nm). [1] Among them, UVA and UVB are mainly derived from the natural environment. They account for 90%-95% and 5%-10% of solar radiation, respectively, and are of the part of sunlight that leads to sunburn, skin cancers, and cataracts. [2][3][4][5] Until now, many photodetectors, which detect UV radiation with wavelengths longer than 280 nm, have been integrated into weather forecast programs to prevent UVA andThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Growth of Low-defect Si-Doped Ga2O3 Film on Fluorine-doped Tin Oxide Substrate for Self-powered and High-performance Ultraviolet Photodetector

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Controlling Threshold and Resistive Switch Functionalities in Ag‐Incorporated Organometallic Halide Perovskites for Memristive Crossbar Array

“…These days, research about HPs-based semiconductors verifies exotic characteristics such as tunable bandgap, fast ion migration, tunable majority carrier, and super-flexibility, proving the potential as the next generation of semiconductor material in electronic devices. [35][36][37][38][39] Our previous works have reported HPs-based resistive switching memory devices operating in ultralow voltage and artificial synaptic devices. [40][41][42][43][44] This characteristic stems from a low activation energy barrier for the movement of vacancies and ions in the halide matrix.…”

Self-Powered Photodetector Based on Ag/CH3NH3PbI3/C Asymmetric Dual-Terminal Device

“…One of these fields is to develop high-performance photodetectors by utilizing cost-effective materials. Additionally, the miniaturization and portability of electronic devices have led to the demand for self-powered photodetection systems capable of operating under passive conditions. , To meet the requirement, harnessing renewable energy from the surroundings has emerged as a potential solution. − Among the energy harvesting technologies, one-dimensional (1D) nanostructures have gained prominence due to their simple structure and abundant surface states. , They have shown exceptional performance as photoactive layers, highlighting their potential in photodetection applications. − …”