Improving the optoelectronic properties of single-crystalline antimony sulfide rods through simultaneous defect suppression and surface cleaning

Low-dimensional semiconductors can be used for the fabrication of various optoelectronic devices due to their fascinating structures and physical properties. Herein, one-dimensional single-crystalline antimony sulfide (Sb2S3) rods with tunable lengths/diameters were synthesized via a hydrothermal approach followed by thermal treatment. Comprehensive structural characterizations and theoretical simulations revealed that annealing in H-2/Ar can further remove the sulfur residue on the pristine Sb2S3 surface and improve the crystallinity of the rods with a reduced number of structural defects. The resultant high-quality Sb2S3 rods manifested impressive optoelectronic properties. As a proof-of-concept, a single Sb2S3 rod photodetector was fabricated and tested. The device manifested good response rate (5.10 A W-1), high external quantum efficiency (1130.7%), fast rise/decay time during on/off switching (4.03/4.08 ms), and a good detection rate (2.16 x 10(10) Jones, herein Jones are the unit of detection rate by default). The photodetector also displayed a high switching ratio of 109.8 under 560 nm monochromatic light. The photodetection performance is superior or comparable to recently reported systems. Our results highlight the importance of the fine control of crystallinity, purity and defects (density) of semiconductors through rational post treatment for optoelectronic applications. The Sb2S3 rods may also find potential applications in other optoelectronic devices.

Automated summary

One-dimensional single-crystalline antimony sulfide (Sb2S3) rods with tunable lengths/diameters were synthesized via a hydrothermal approach followed by thermal treatment. The high-quality Sb2S3 rods showed impressive optoelectronic properties, and a single Sb2S3 rod photodetector demonstrated good response rate, high quantum efficiency, fast rise/decay time, and a high switching ratio under 560 nm monochromatic light.