Eco-friendly schottky photodetectors enabled by Zingiber officinale extract: broadband UV–Vis–NIR response and high EQE performance

Sustainable optoelectronics increasingly seek eco-friendly semiconductor materials, yet natural compounds for broadband photodetectors remain underexplored. This study investigates whether Zingiber officinale (ginger) extract can function as an effective interlayer in UV–Vis–NIR Schottky photodetectors. The extract was obtained via supercritical CO₂ extraction, a solvent-free and energy-efficient method. Structural, optical, and morphological properties of the Z. officinale interlayer were characterized using XRD, UV–Vis, FTIR, SEM, and EDX, revealing a wide optical band gap of 2.78 eV. Devices incorporating the extract exhibited a high rectifying ratio (11288 at ± 3 V) and strong broadband photoresponse from 351 to 1600 nm. Peak responsivity and external quantum efficiency were recorded in the visible range at zero bias (0.053 A/W, 14.5% EQE), with notable performance at 351 nm (15.9% EQE). While responsivity decreased in the near-infrared, measurable detection persisted up to 1600 nm. Low noise-equivalent power and high detectivity in the visible spectrum further confirmed efficient light detection. These results demonstrate that Z. officinale extract is a viable natural interlayer for sustainable, self-powered UV–Vis–NIR photodetectors.