Synthesis of Bi2S3–Bi2O3 composites and their enhanced photosensitive properties

Abstract

Bi₂S₃–Bi₂O₃ composites were synthesized by a facile hydrothermal method with surfactant as template. The structure and morphology of the as-synthesized products were characterized in detail. The photosensitive behavior of the Bi₂S₃–Bi₂O₃ composites was investigated carefully. Under the illumination of a 650 nm laser in air or vacuum, the device displayed enhanced photosensitive performance compared to the pure Bi₂S₃, pure Bi₂O₃ and mechanical mixture of Bi₂S₃ and Bi₂O₃ based devices. The photoswitch ratio (I_photo/I_dark) was as high as 30 in a vacuum with fast photoresponse speed, which indicated their potential applications in manufacturing photodetectors and optoelectronic devices. The possible mechanism of enhanced photosensitivity was also proposed.