2025 Theses Doctoral

Doping Two-Dimensional Layered Materials

Yu, Jessica Tong

This dissertation describes the doping of two-dimensional layered materials and the characterization of their resulting properties. The field of two-dimensional materials has experienced great progress. It is important for us to develop methods to systematically tune their properties for practical application. Additionally, by engineering the properties of two-dimensional materials, we can uncover new insights into their physical and chemical behavior.

Chapter 1 begins with a general overview of two-dimensional materials and their unique layered structure and resulting characteristics. Tuning knobs for modifying these materials are discussed, and methods for doping are introduced. This chapter will also give an introduction to superatomic material systems and kagome material systems, which will be the focus of the dissertation.

Chapter 2 describes an electrochemical method to dope superatomic Re₆Se₈Cl₂. Using electrical transport measurements, we show successful electron doping. By characterizing the material after electrochemical treatment, we show we can significantly improve its transport properties without altering the superatomic structure.

Chapter 3 explores using soft topochemistry to deintercalated the alkali metal atoms and dope the kagome semiconductor Cs₂Ni₃Se₄. Using a combination of characterization techniques, and magnetism and transport measurements, we show that we can use the deintercalation reaction as a tuning knob for the resulting charge ordering.