Abstract
MoS2 has been studied intensively during recent years as a semiconducting material in several fields, including optoelectronics, for applications such as solar cells and phototransistors. The photoresponse mechanisms of MoS2 have been discussed but are not fully understood, especially the phenomenon in which the photocurrent slowly increases. Here, we report on a study of the photoresponse flash-light-processed MoS2 films of different thicknesses and areas. The photoresponse of such films under different light intensities and bias voltages was measured, showing significant current changes with a quick response followed by a slow one upon exposure to pulsed light. Our in-depth study suggested that the slow response was due to the photothermal effect that heats the MoS2; this hypothesis was supported by the resistivity change at different temperatures. The results obtained from MoS2 films with various thicknesses indicated that the minority-carrier diffusion length was 1.36 µm. This study explained the mechanism of the slow response of the MoS2 film and determined the effective thickness of MoS2 for a photoresponse to occur. The method used here for fabricating MoS2 films could be used for fabricating optoelectronic devices due to its simplicity.
Highlights
Molybdenum disulfide (MoS2) is a layered transition metal dichalcogenide (TMDC), in which the molecular layers are stacked via van der Waals forces[1]
MoS2 was first exfoliated in a pH 1.0 nitric acid solution and filtered and rinsed on polyvinylidene fluoride (PVDF) films
To further study the influence of the geometry of the MoS2 films, the films were cut into smaller pieces, and the photoresponse was measured again
Summary
Molybdenum disulfide (MoS2) is a layered transition metal dichalcogenide (TMDC), in which the molecular layers are stacked via van der Waals forces[1]. We produced large-area MoS2 films with various thicknesses using a protocol that combines acid exfoliation, vacuum filtration, flash-light processing and polishing. Such films had a higher photoresponse than the films fabricated on glass without flash-light processing (Figure S4 in the supporting information).
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
