Interfacial engineering enables polyaniline-decorated bismuth sulfide nanorods towards ultrafast metal–semiconductor-metal UV-Vis broad spectra photodetector

Herein, we reported photoelectric measurements of the polyaniline decorated with bismuth sulfide (Bi₂S₃/PANI) nanohybrid based metal-semiconductor-metal (MSM) device in the broad electromagnetic (EM) spectrum from ultraviolet (UV) to visible (Vis) range. Bi₂S₃ nanorods decorated with π-conjugated polymer PANI were utilized as photodetection devices has a wide range of applications in imaging and communication. In such a novel structure, the fast electron transfer at the interface of Bi₂S₃ and PANI occurs, which enhances the performance of the photodetectors. Current–voltage (I–V) characteristics of the MSM photodetector device of Bi₂S₃/PANI nanohybrid show good ohmic nature. This photodetector device offers the highest external quantum efficiency (EQE) 10⁴% in the UV and visible regions. It also shows the greatest detectivity of the order 10¹⁴ Jones. The photoresponsivity of the Bi₂S₃/PANI nanohybrid photodetector device shows 270 mAW⁻¹ in UV region and 1270 mAW⁻¹ in visible region at only 1 V with the minimum optical signal of 50 µWcm⁻². The highest photoresponsivity of the Bi₂S₃/PANI nanohybrid photodetector offers 26,760 mAW⁻¹ and 13,250 mAW⁻¹ for the UV and visible spectra, respectively. The higher values of the LDR are 64.31 dB and 58.21 dB in the UV and visible regions, respectively, at 100 V with the lowest illumination intensity. The minimum value of NEP found in the order of 10⁻⁹ W which is the lowest value, suggests that the nanohybrid material is perfect for low-intensity photon signals. This work provides simple and effective method for the preparation of MSM photodetector technology exhibits a magnificent performance in the UV-to-Vis region.