Synthesis of Submillimeter-Scale Single Crystal Stannous Sulfide Nanoplates for Visible and Near-Infrared Photodetectors with Ultrahigh Responsivity

Layered 2D semiconductors, such as graphene and transition-metal dichalcogenides (TMDs), are receiving intensive attention owing to their great performance in electronic and optoelectronic application during the past few years. Among them, SnS has similar anisotropy to black phosphorus and high photoresponse in the near infrared range, rendering it as an ideal candidate for infrared photodetectors. In this work, large-size (up to 330 mu m) and high-quality single-crystalline SnS nanoplates are synthesized successfully via controlled chemical vapor deposition technique and characterized by field-emission scanning electron microscopy, X-ray diffraction, confocal Raman system, atomic force microscope, transmission electron microscopy, and photoluminescence spectroscopy. Photodetectors based on as-grown SnS nanoplates are fabricated with back-gated field effect transistors (FETs) configuration, exhibiting a high mobility of 17.1 cm(2) V-1 s(-1). Photodetectors based on the SnS FETs demonstrate excellent optoelectronic performance both in visible and near-infrared spectral range. Typically, photoresponsivity of 197.7 A W-1, photoresponse time of 39 ms, and external quantum efficiency of 6.06 x 10(4)% are exhibited under the irradiation of 405 nm laser. The wide response range and ultrahigh sensitivity make the large-area single crystal SnS nanoplate a promising candidate for future application in optoelectronics.