This thesis is dedicated to the experimental study of charge transfer and molecular interactions on graphene on iridium substrate, examining in detail the effects of oxygen and dysprosium intercalation combined with the deposition of organic molecules (HMTP and HATCN).

Throughout the project, the student worked independently and with her own initiative. She approached both the experimental work and the subsequent data analysis with great proactivity and responsibility.

The thesis is extensive and systematic. The student successfully covered all relevant combinations of intercalation and molecular doping, thereby fulfilling all the tasks and objectives set out in the thesis assignment. The results presented are supported by solid experimental data and carry strong value for future work projects.

From a formal and linguistic standpoint, the thesis is clearly written, features a logical structure, and distinctly separates the author's own contributions from the cited literature.

The thesis meets all the requirements of a master's thesis and I recommend it for defense.

The thesis of Bc. Šebestová is an experimental study focused on charge transfer and molecular interactions in graphene grown on iridium. The doping effects induced by oxygen and dysprosium intercalation are investigated, as well as the changes in doping and interactions following the deposition of organic molecules such as HMTP and HATCN. The work also examines the combined effects of intercalation and molecular deposition.

The thesis is clearly written, technically sound, and extensive, covering all relevant combinations of intercalation and molecular doping. The conclusions are solid and well supported by the experimental data. The thesis fulfilled all stated objectives. The text clearly distinguishes between the student's original contributions and information sourced from the literature. From a formal perspective, the work satisfies the requirements for a Master's thesis.

Therefore, I recommend the thesis for defense.

I have one comment and two questions.

Comment

The statement that graphene was first isolated in 2004 is historically inaccurate. Before the 2004 breakthrough, monolayer graphite/graphene-related systems had already been intentionally prepared and studied, particularly on SiC, metal surfaces, and transition-metal carbides, with experimental work dating back at least to the 1970s and 1980s. By the end of the 1990s, this earlier research had already been summarized in review papers on monolayer graphite on metals and carbides. The term graphene itself was introduced by Boehm, Setton, and Stumpp in the 1980s and was later adopted in IUPAC nomenclature. Thus, 2004 should not be presented as the year of graphene’s first isolation or discovery. Rather, it marks the beginning of the modern graphene boom, initiated by the demonstration of high-quality, electrically addressable graphene and the rapid expansion of research into its electronic properties. A more accurate formulation would therefore be: “Since 2004, graphene has attracted rapidly increasing attention,” or “The modern era of graphene research began in 2004.”

The following literature supports these historical perspectives:

Gall, N. R., Rutkov, E. V., and Tontegode, A. Y. Two-dimensional graphite films on metals and their intercalation. International Journal of Modern Physics B, 11(16):1865–1911, 1997. doi: 10.1142/S0217979297000976.

Oshima, C., and Nagashima, A. Ultra-thin epitaxial films of graphite and hexagonal boron nitride on solid surfaces. Journal of Physics: Condensed Matter, 9(1):1–20, 1997. doi: 10.1088/0953-8984/9/1/004.

Boehm, H. P., Setton, R., and Stumpp, E. Nomenclature and terminology of graphite-intercalation compounds: Report by a subgroup of the International Committee for Characterization and Terminology of Carbon and Graphite on suggestions for rules for the nomenclature and terminology of graphite-intercalation compounds. Synthetic Metals, 11(6):363–371, 1985. doi: 10.1016/0379-6779(85)90068-2.

Takahashi, T., Tokailin, H., and Sagawa, T. Angle-resolved ultraviolet photoelectron spectroscopy of the unoccupied band structure of graphite. Physical Review B, 32(12):8317–8324, 1985. doi: 10.1103/PhysRevB.32.8317.

Van Bommel, A. J., Crombeen, J. E., and Van Tooren, A. LEED and Auger electron observations of the SiC(0001) surface. Surface Science, 48(2):463–472, 1975. doi: 10.1016/0039-6028(75)90419-7.

Forbeaux, I., Themlin, J. M., and Debever, J. M. Heteroepitaxial graphite on 6H-SiC(0001): Interface formation through conduction-band electronic structure. Physical Review B, 58(24):16396–16406, 1998. doi: 10.1103/PhysRevB.58.16396. Topics for thesis defence:

1. What spectroscopic evidence allows one to distinguish oxygen intercalated beneath graphene from oxygen adsorbed on top of graphene? In particular, how would the O 1s and C 1s spectra differ in the two cases?
2. In Fig. 8.3g, after HMTP deposition on Gr/Dy/Ir(111), the Dirac cone remains clearly visible, whereas in Fig. 8.1f, after HMTP deposition on non-intercalated Gr/Ir(111), the Dirac cone is no longer clearly resolved. Could the disappearance of the Dirac cone in Fig. 8.1f simply result from a thicker HMTP layer?