High-Quality SbSI Nanowires via Chemical Vapor Transport for Anisotropic Polarized Photodetection

Polarized photodetectors, critical for optical radar, biomedical imaging, and quantum communication, require materials with high dichroic ratios and robust stability. Low-dimensional materials like black phosphorus (BP) and transition metal dichalcogenides (TMDs) offer intrinsic anisotropy ideal for polarization-sensitive detection, yet suffer from poor air stability and scalability. V–VI–VII compounds, such as SbSI, SbSeI, and BiSI, have emerged as promising alternatives due to their ferroelectricity, moderate bandgaps (1.5–2.5 eV), and structural anisotropy. However, conventional synthesis methods (e.g., hydrothermal and sonochemical) often yield defect-rich crystals, limiting performance. Chemical vapor transport (CVT), leveraging precise temperature gradients and transport agents, produces high-quality, low-defect SbSI nanowires, addressing these challenges. This study optimizes CVT to synthesize SbSI nanowires, achieving a dichroic ratio of ∼2.0 and a responsivity of 0.16 A/W, demonstrating their potential for advanced optoelectronics.