Synthesis of Thin Bi9O7.5S6 Nanosheets for Improved Photodetection in a Wide Wavelength Range

• Published in: Chemistry, an Asian journal an Asian journal, 2021-11, Vol.16 (22), p.3748-3753
• Main Authors: Yi, Ronghua, Wang, Jin, Yue, Xiaoping, Liang, Yan, Li, Zhuoyao, Sheng, Huixiang, Guan, Mengdan, Zhu, Yameng, Sun, Qizeng, Wang, Li, Huang, Xiao, Lu, Gang
• Format: Article
• Language: English
• Subjects: bismuth oxysulfide nanosheet; photodetection; solvothermal reaction; thin nanosheet; wide wavelength range
• ISSN: 1861-4728; 1861-471X
• DOI: 10.1002/asia.202100963

Bismuth‐based compounds possess layered structures with a variety of stacking modes, endowing the compounds with diverse properties. As one type of bismuth oxysulfides, Bi9O7.5S6 nanocrystals has great applications in photodetection; however, the responsivity of bulky Bi9O7.5S6 is limited due to the poor charge separation. Herein, single‐crystalline Bi9O7.5S6 thin nanosheets are successfully synthesized by using a solvothermal method. The thickness of the obtained Bi9O7.5S6 nanosheets is down to 15 nm and can be easily tuned by varying the reaction period. Moreover, the Bi9O7.5S6 nanosheets show strong light absorption in the visible and near infrared range, making it a promising candidate in optoelectronics. As a demonstration, the thin Bi9O7.5S6 nanosheets are used as active layer in an optoelectronic device, which exhibits sensitive photoelectric response to light in a wide range of 400–800 nm. The responsivity of the device reaches up to 1140 μA W−1, and the performance of the device is stable after long‐period illumination. This work demonstrates a great potential of the thin Bi9O7.5S6 nanosheets in optoelectronic devices, and these nanosheets may also be extended to various optoelectronic applications. Single‐crystalline Bi9O7.5S6 thin nanosheets were successfully synthesized by using a solvothermal method. The thin Bi9O7.5S6 nanosheets are used as active layer in an optoelectronic device, which exhibits a sensitive photoelectric response to light in a wide range of 400–800 nm.