Effect of morphology and stacking on atomic interaction and magnetic characteristics in two-dimensional H-phase VS2 few layers

• Published in: Journal of materials science 2022-03, Vol.57 (10), p.5873-5884
• Main Authors: Zhang, Shuo, Chang, Pu, Zhang, Yunfei, Xu, Xiaomin, Guan, Lixiu, Tao, Junguang
• Format: Article
• Language: English
• Subjects: Atomic interactions; Characterization and Evaluation of Materials; Chemical synthesis; Chemical vapor deposition; Chemistry and Materials Science; Classical Mechanics; Crystallography and Scattering Methods; Electronic devices; Electronic Materials; Interlayers; Magnetic properties; Many body problem; Materials Science; Morphology; Polymer Sciences; Room temperature; Sapphire; Shear modulus; Solid Mechanics; Stacking; Transition metal compounds; Valence band
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-022-06904-7

Recently, the research of two-dimensional layered transition metal dichalcogenides has made great progress due to their high potential in advanced electronic devices. In this work, H- phase VS 2 atomic layers with different morphologies and stacking orders were successfully synthesized on sapphire via chemical vapor deposition. The H- phase VS 2 shows semiconductor characteristic with its valence band maximum located ~ 0.25 eV below the Fermi level. Interlayer many-body interactions are strongly stacking-dependent, leading to distinguished intensity ratio between the breathing and shear modes, 2.99 ± 0.94 for AA, and 1.72 ± 0.26 for AB stacking. The intralayer S-V interaction (force constant: 2.80–3.54 × 10 21  N/m 3 ) is two orders of magnitude larger than the interlayer S–S interaction (force constant: 1.98–6.70 × 10 19  N/m 3 ). The shear modulus is further derived to be ~ 12.8 GPa, ~ 30% smaller than that of MoS 2 . The prepared VS 2 film exhibits obvious magnetic behavior at room temperature with the attenuation distance of ~ 16–25 nm in out-of-plane direction. The morphology dependent magnetism and stability investigations indicate that the measured magnetic behaviors of the sample have a certain degree of extrinsic contributions, which may settle down some experimental controversies about the magnetic behaviors in this specific system.