Substrate-mediated growth of oriented, vertically aligned MoS2 nanosheets on vicinal and on-axis SiC substrates

Bradford, Jonathan; Zaganelli, Aurora; Qi, Dongchen; Zebardastan, Negar; Shafiei, Mahnaz; MacLeod, Jennifer; Motta, Nunzio

Abstract

The layer- and morphology-dependent properties of two-dimensional molybdenum disulfide (MoS2) have established its relevance across broad applications in electronics, optoelectronics, sensing, and catalysis. Understanding how to manipulate the material growth to achieve the desired properties is the key to tailoring the material towards a specific application. In this work, we investigate the growth of vertically standing MoS2 nanosheets by chemical vapor deposition on vicinal and on-axis 4H-SiC (0001) substrates. In both cases the MoS2 flakes exhibit three preferred orientations, aligning with the substrate directions due to strain minimization of a MoO2 intermediate phase. Whereas MoS2 grown on vicinal SiC substrates exhibits strict near-vertical alignment, scanning electron microscopy and near-edge X-ray absorption fine structure (NEXAFS) measurements indicate a near-random vertical orientation when MoS2 is grown on on-axis SiC. Photoemission spectroscopy and NEXAFS measurements indicate the presence of defects and disordered edges which establish the suitability of the material for applications in sensing and catalysis.

Citation

Bradford, J., Zaganelli, A., Qi, D., Zebardastan, N., Shafiei, M., MacLeod, J., & Motta, N. (2021). Substrate-mediated growth of oriented, vertically aligned MoS2 nanosheets on vicinal and on-axis SiC substrates. Applied Surface Science, 552, Article 149303. https://doi.org/10.1016/j.apsusc.2021.149303

• Journal Article Type: Article
• Acceptance Date: Feb 9, 2021
• Online Publication Date: Feb 21, 2021
• Publication Date: Jun 30, 2021
• Deposit Date: Apr 21, 2021
• Publicly Available Date: Feb 22, 2022
• Journal: Applied Surface Science
• Print ISSN: 0169-4332
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 552
• Article Number: 149303
• DOI: https://doi.org/10.1016/j.apsusc.2021.149303
• Keywords: Surfaces, Coatings and Films
• Public URL: https://nottingham-repository.worktribe.com/output/5486959
• Publisher URL: https://www.sciencedirect.com/science/article/abs/pii/S0169433221003792