Thursday May 28 at 3:00 pm (Moscow time)
Topic: Epitaxial Growth of Next-Generation 2D Materials
Presenter: Marko Kralj, Institute of Physics, Bijenička 46, Zagreb, Croatia
Long before graphene gained fame in 2004, its epitaxial growth had already been realized in surface science studies focused on the adsorption and decomposition of hydrocarbons on metal substrates [1]. Surface parameters play a crucial role in the synthesis of various two-dimensional (2D) materials, including graphene, transition metal dichalcogenides (TMDs), and novel homoelemental materials. The broad parameter space governing growth is influenced by factors such as surface chemical reactivity, lattice parameters, anisotropy, surface alloying, and others. In this talk, I will present recent research conducted by the Surfaces, Interfaces and 2D Materials research group in Zagreb. The focus will be on several examples of epitaxially grown atomically thin 2D materials and heterostructures with potential for novel applications, highlighting the unique properties of these systems.
In the case of 2D borophene (Bo), we have developed novel growth protocol, and in situ and ex situ characterization, and manipulation methods. X-ray photoelectron spectroscopy (XPS) and scanning tunneling spectroscopy (STS) reveal inhomogeneous binding of Bo to Ir, resulting in a stripe-like structure. This structure acts as a one-dimensional grating, inducing Umklapp scattering of photoelectrons detected in ARPES experiments [2]. Furthermore, our results demonstrate that ex situ deterministic manipulation of Bo layers is feasible despite their inherent chemical and mechanical instability, advancing borophene research and potential applications [3]. Finally, we address lithiation of Bo monolayer showcasing advantages and challenges of alkali-metal decoration of borophene and provide guidelines for future borophene functionalization strategies [4].
We will also address TMD–graphene heterostructures. Our goal was to achieve quasi-freestanding TMD systems and to characterize the effects of vertical and lateral stacking of MoS₂ and WS₂ [5]. Additionally, we explored how intentional self-intercalation during growth enables efficient in situ chemical and physical engineering of material properties, particularly the electronic band structure [6].
[1] T.A. Land, et al., Surf. Sci. 264, 261-270 (1992).
[2] S. Kamal, et al., ACS Appl. Mater. Interfaces 15, 57890–57900 (2023).
[3] B. Radatović, et al., ACS Appl. Mater. Interfaces 14, 21727–21737 (2022).
[4] S. Kamal, et al., submitted (2026).
[5] B. Pielić, et al., ACS Appl. Mater. Interfaces 13, 50552–50563 (2021).
[6] B. Pielić, et al., npj 2D Mater. Appl. 8, 61 (2024).
Zoom link: https://espci.zoom.us/j/84655696270?pwd=OUjQ0Knj1D54cLIEZDFm7pgXoR9Oib.1
ID: 846 5569 6270
Passcode: 825893
