Single Zn2GeO4 nanowire high-performance broadband photodetector

Broadband photodetectors have attracted considerable attention owing to their commercial and military applications. We report using a single Zn2GeO4 nanowire for high-performance broadband photodetectors. The Zn2GeO4 nanowires are stoichiometric, single crystal rhombohedral structure with a high concentration of intrinsic defects. The photodetector exhibits high photocurrent, high normalized gain, high detectivity, and a broad spectral response from UV to visible light. The photoresponsivities of 404 A W−1 at the UV wavelength of 325 nm, 505 A W−1 at the visible light of 405 nm, 606 A W−1 at 532 nm, and 336 A W−1 at 633 nm have been achieved. The detectivity of a device is ranging from 4.3 × 1011 to 1.2 × 1012 Jones in the spectral range from UV to visible. The broadband photoresponse characteristics of a single Zn2GeO4 nanowire photodetector are attributed to the high surface-to-volume ratio, wide bandgap, and defect-rich nature of Zn2GeO4 nanowire. In addition, the oxygen-sensitized photoconduction mechanism has been proposed. The results suggest that Zn2GeO4 nanowires are promising materials for a broadband flexible photodetector under harsh environments.