Self-Powered Solar-Blind Photodetectors Based on Vertically Aligned GaN@Ga₂O₃ Core–Shell Nanowire Arrays

Abstract

The self-powered photodetector has recently received wide attention as a fundamental component of energy-saving optoelectronic systems. In this study, the GaN@Ga 2 O 3 core−shell nanowire arrays (NAs) were used as the photoanode for the selfpowered solar-blind photoelectrochemical-type photodetectors (PEC-PDs). The vertically aligned GaN@Ga 2 O 3 core−shell NAs on the GaN template was fabricated by the inductively coupled plasma etching combined with the thermal oxidation process. Under 255 nm illumination without an external power supply, the device exhibits a maximum responsivity of 93.48 mA/W, yielding a high external quantum efficiency of 45.54%, which shows one of the best values among the reported solar-blind Ga 2 O 3 -based PEC-PDs. Furthermore, the device shows a fast response speed (τ r = 25 ms, τ d = 5 ms) and good stability. Such excellent performance under zero bias may benefit from the superior light-absorbing capability of the vertical NAs, the good solid/liquid contact realized by the nanostructures, and the efficient photogenerated carrier separation driven by the double built-in electric field. This work provides a simple and feasible route to construct high-performance solar-blind Ga 2 O 3based PEC-PDs.

Facile Semiconductor p–n Homojunction Nanowires with Strategic p-Type Doping Engineering Combined with Surface Reconstruction for Biosensing Applications

“…Notably, in Table 1 , we also summarized and included different GaN nanowires-based photoelectrochemical-type photosensors. Different types of GaN nanowires in the form of heterojunction with other materials have been formed and reported, such as GaN/AlGaN [ 46 ], GaN/Pt [ 47 ], GaN/Cu [ 8 ], GaN/Cu 2 O [ 48 ], GaN/AuNC [ 49 ], GaN/CsPbBr 3 [ 50 ], and GaN/Ga 2 O 3 [ 51 ]. Impressively, our device exhibits a high responsivity with remarkable device stability which is superior to that of other reported PEC-type photosensors, demonstrating its great potential for future sensitive, sustainable optoelectronic sensing systems.…”

A nanoflower-like GaSe/β-Ga2O3 based heterostructure for highly efficient self-powered broadband photodetectors

“…Deep ultraviolet photodetectors (PDs) have received considerable attention because of their use in many key applications, such as detecting flames, tracking missiles, communicating with spacecraft, ozone hole monitoring, etc. 1–6 These PDs have been the focus of considerable study because of their ability to detect weak optical signals accurately and precisely in the solar-blind domain (wavelength < 280 nm). Numerous wide-bandgap semiconducting materials, such as AlGaN, diamond, ZnMgO, and β-Ga 2 O 3 , are now the primary focus for developing solar-blind photodetectors.…”

Achieving a High-Responsivity and Fast-Response-Speed Solar-Blind Photodetector for Underwater Optical Communication via AlGaN/AlN/GaN Heterojunction Nanowires

“…Ultraviolet photodetectors (UV PDs) have attracted extensive attention due to their potential applications in both military and civilian applications, such as fire alarms, missile detection, secure communication, and various optoelectronic fields. , At the same time, energy-saving, sustainable, and self-powered devices have been a significant exploration direction for next-generation highly efficient photonic systems in recent decades. , Based on the operating environment, UV detectors can be categorized into solid-type UV PDs, − liquid-type UV PDs, − and quasi-solid-type UV PDs. − Traditionally, solid-state UV PDs are usually suggested to introduce external bias to obtain high responsivity. Additionally, the complex and expensive fabrication process served for solid-state UV PDs, which is unfavorable to achieving low-cost and high-performance photodetection.…”