Ultrafast Self-Powered\nCopper Oxide Composite-Based\nVis-NIR Photodetector Probe

Abstract

Self-powered photodetectors are gaining attention due\nto their\nsimplistic fabrication and easy system integration. This paper presents\nthe feasibility of realizing a Cu₂O(CuO) working electrode\n(WE)-based photoelectrochemical (PEC)-type photodetector (PD) probe\nwith an arrangement of Cu/NaCl (W)/Cu₂O(CuO), where the\ncopper oxide composite electrode is fabricated using thermal treatment\nof Cu. It is observed that under zero bias and 470 nm irradiation,\nthe photodetector can produce a responsivity and a specific detectivity\nof up to 20.11 mA W⁻¹ and 2.62 × 10⁸ Jones, respectively. Further, it can produce a photocurrent of up\nto 5 μA under 33.78 mW cm^–2 optical power\ndensity while having a dark current of 50 nA. Moreover, the photodetector\nalso shows a minimal rise and a recovery time of 20 and 140 ms, respectively.\nWith a realized high responsivity, this proposed photodetector holds\nexcellent potential for next-generation optoelectronic sensor applications.