An HBS@GaSe:Dy-Based Organic/Inorganic Hybrid Heterojunction for High-Performance Multicolor Photodetectors

Herein, a multicolor heterojunction photodetector was fabricated using organic Hibiscus sabdariffa (HBS) material and two-dimensional (2D) dysprosium-doped GaSe as an HBS@GaSe design. For the fabricated hybrid heterojunction, multicolor broadband photodetection covering UV-vis-NIR spectra is observed for the light power density of 7 mW/cm2, and the optoelectronic properties of the heterojunction photodetector were studied in detail. Electrooptical measurements were performed with I-V measurements under white light as well as under 365 nm violet (UV), 590 nm (yellow), and 850 nm IR light irradiation. For this purpose, the key parameters of a photodetector, such as ON/OFF ratio, responsivity, specific detectivity, NPDR, NEP, and EQE, have been calculated. Under illumination of 590 nm, a maximum ON/OFF ratio of 1.8 × 104 was observed for −1.76 V reverse bias. The photodetectors exhibit excellent photoresponse properties, with a high responsivity of 2166 mA/W, an EQE of 736%, and a high detectivity of 6.81 × 1012 Jones at 590 nm. The high responsivity was attributed to the interfacial traps, enhancing the photoconductivity gain. Our work suggests that the HBS@GaSe-based organic/inorganic hybrid heterojunction is a promising candidate for ultrasensitive multicolor photodetection.