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 (Iphoto/Idark) 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.