Thickness-dependent bandgap and electrical properties of GeP nanosheets
- Authors
- Kim, Doyeon; Park, Kidong; Shojaei, Fazel; Debela, Tekalign Terfa; Kwon, Ik Seon; Kwak, In Hye; Seo, Jaemin; Ahn, Jae Pyoung; Park, Jeunghee; Kang, Hong Seok
- Issue Date
- 21-7월-2019
- Publisher
- ROYAL SOC CHEMISTRY
- Citation
- JOURNAL OF MATERIALS CHEMISTRY A, v.7, no.27, pp.16526 - 16532
- Indexed
- SCIE
SCOPUS
- Journal Title
- JOURNAL OF MATERIALS CHEMISTRY A
- Volume
- 7
- Number
- 27
- Start Page
- 16526
- End Page
- 16532
- URI
- https://scholar.korea.ac.kr/handle/2021.sw.korea/64078
- DOI
- 10.1039/c9ta04470a
- ISSN
- 2050-7488
- Abstract
- Recently there have been extensive efforts to develop novel two-dimensional (2D) layered structures, owing to their fascinating thickness-dependent optical/electrical properties. Herein, we synthesized thin GeP nanosheets that had a band gap (E-g) of 2.3 eV, which is a dramatic increase from the value in the bulk (0.9 eV) upon exfoliation. This E-g value is close to that of the GeP monolayer predicted by first-principles calculations (HSE06 functional). The calculations also indicate a strong dependence of E-g on the number of layers (2.306, 1.660, 1.470, and 1.397 eV for mono-, bi-, tri-, and tetralayers, respectively), and that the band edge positions are suitable for water splitting reactions. Field-effect transistor devices were fabricated using the p-type GeP nanosheets of various thicknesses, and the devices demonstrated a significant decrease in the hole mobility but an increased on-off ratio as the layer number decreased. The larger on-off ratio (10(4)) for the thinner ones is promising for use in novel 2D (photo)electronic nanodevices. Further, liquid-exfoliated GeP nanosheets (thickness = 1-2 nm) deposited on Si nanowire arrays can function as a promising photoanode for solar-driven water-splitting photoelectrochemical (PEC) cells. Based on the calculated band offset with respect to the Fermi levels for the two half-reactions in the water splitting reaction, the performance of the PEC cell can be explained by the formation of an effective p-GeP/n-Si heterojunction.
- Files in This Item
- There are no files associated with this item.
- Appears in
Collections - Graduate School > Department of Advanced Materials Chemistry > 1. Journal Articles
![qrcode](https://api.qrserver.com/v1/create-qr-code/?size=55x55&data=https://scholar.korea.ac.kr/handle/2021.sw.korea/64078)
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.