Van der Waals, or layered, materials offer a flexible platform to tune properties via exfoliation down to the single-or few-layer limit; they are at the forefront of cutting-edge materials science and engineering research because of the innumerable ways to tune materials as a function of thickness or composition. Due to quantum confinement effects, the band structures of many layered materials undergo drastic changes as they are thinned down, resulting in transitions from direct to indirect

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... gaps, modifications of the size of the band gap and emergence of exotic physics (e.g., spintronics, valleytronics, charge density waves, quantum spin liquids). Furthermore, exfoliation results in increased surface area, ideal for applications in areas like sensing, hydrogen evolution, or energy storage with the resulting nanosheets. In addition, due to their atomically flat nature, they are amendable to the formation of heterostructures, further diversifying the number of ways exfoliated materials can be utilized. Among various top-down techniques facilitating isolation of mono-, bi-, and multilayers of layered materials of interest, liquid-phase exfoliation is one of the most popular as it offers a relatively high-yield production and ease of further properties tailoring based on solution-phase post-processing (e.g., size selection), enabling large-scale industrial production. This thesis will focus on the liquid-phase exfoliation of two-dimensional materials as a whole before delving in detail into two post-transition metal dichalcogenide materials, germanium