Controlled growth of high-quality β-Ag2Se nanowires and their applications in near-infrared photodetection

This work reports the controlled growth of single-crystalline β-Ag 2 Se nanowires and their application in near-infrared photodetection. High-quality Ag 2 Se nanowires with an orthorhombic crystal structure are grown via the chemical vapor deposition method with a length up to 32.8 μ m and a diameter down to 52.1 nm. By fine-tuning the growth parameters such as total tube inner pressure and precursor temperature, the length of Ag 2 Se nanowires can be precisely controlled. A dynamic growth model is also introduced to interpret the growth mechanism of Ag 2 Se nanowires. Two-terminal photodetectors based on single Ag 2 Se nanowire are fabricated and show competitive photodetection performance compared to that of other silver chalcogenide nanomaterial-based photodetectors. At room temperature, the fabricated Ag 2 Se nanowire-based photodetector exhibits a broadband response range of 400–1064 nm at a bias voltage of 2 V, while the peak photo-response performance is obtained in the near-infrared region. Under 830 nm light illumination, the maximum responsivity, specific detectivity, rise time and decay time are measured and calculated to be 99.6 mA/W and 4.01 × 10 6 Jones, 23.84 ms and 47.6 ms, respectively, demonstrating its potential in uncooled near-infrared photodetector applications. • High-quality Ag 2 Se nanowires with an orthorhombic crystal structure were grown via the chemical vapor deposition method. • The length of Ag 2 Se nanowires was precisely controlled by fine-tuning the total tube inner pressure and precursor temperature. • A dynamic growth model was introduced to interpret the growth mechanism of Ag 2 Se nanowires. • A NIR photodetector based on single Ag 2 Se NW was fabricated, which presents excellent device performance.