2D/1D PbI 2 /Sb 2 S 3 van der Waals heterojunction for highly sensitive and broadband photodetectors

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Vol. 12; no. 9; pp. 3353 - 3364
• Main Authors: Fu, Shili, Liu, Xiaohui, Man, Jiaxiu, Ou, Quanhong, Zheng, Xiaolu, Liu, Zhiyong, Zhu, Ting, Wang, Hong-En
• Format: Journal Article
• Language: English
• Published: 29.02.2024
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/D3TC04279K

Broadband photodetectors have received significant scientific interest due to their high optical gain with low energy consumption. PbI 2 is an important 2D semiconductor material for electronic and optoelectronic devices. However, its limited detection capability towards visible light hinders its wide applications in the optoelectronic field. Herein, we report a novel van der Waals (vdW) 2D/1D PbI 2 /Sb 2 S 3 heterojunction photodetector exhibiting broadband spectral response from 400 to 750 nm. In comparison to individual PbI 2 and Sb 2 S 3 devices, the heterojunction photodetector manifests much higher responsivity (156.3 and 120.4 A W −1 ), external quantum efficiency (4.4 × 10 4 % and 2.1 × 10 4 %), and detectivity (3.16 × 10 13 and 2.45 × 10 12 Jones) under 445 and 730 nm illumination, respectively. Experimental characterizations and theoretical calculations reveal the significantly enhanced photoelectric properties can be primarily ascribed to the effective separation of photogenerated electron/hole pairs facilitated by the type-II vdW heterojunction mediated by defect states. This work can provide some new insights into the fabrication of novel hybrid van der Waals heterojunctions and their applications in the optoelectronic fields.