Enhanced Optical Response of SnS/SnS(2) Layered Heterostructure

The SnS/SnS(2) heterostructure was fabricated by the chemical vapor deposition method. The crystal structure properties of SnS(2) and SnS were characterized by X-ray diffraction (XRD) pattern, Raman spectroscopy, and field emission scanning electron microscopy (FESEM). The frequency dependence photoconductivity explores its carrier kinetic decay process. The SnS/SnS(2) heterostructure shows that the ratio of short time constant decay process reaches 0.729 with a time constant of 4.3 × 10(−4) s. The power-dependent photoresponsivity investigates the mechanism of electron–hole pair recombination. The results indicate that the photoresponsivity of the SnS/SnS(2) heterostructure has been increased to 7.31 × 10(−3) A/W, representing a significant enhancement of approximately 7 times that of the individual films. The results show the optical response speed has been improved by using the SnS/SnS(2) heterostructure. These results indicate an application potential of the layered SnS/SnS(2) heterostructure for photodetection. This research provides valuable insights into the preparation of the heterostructure composed of SnS and SnS(2), and presents an approach for designing high-performance photodetection devices.