Mechanical Characterizations of Two-Dimensional Materials
Master of Science
Two-dimensional materials such as graphene and molybdenum disulfide have shown great potential in thermal, electrical and mechanical applications, so deeper understandings in their mechanical behaviors are of great significance. Quantitative in situ tensile testing of suspended graphene synthesized by chemical vapor deposition (CVD) was carried out using a combination of a quantitative in-SEM nanoindenter and a micromechanical device. Pre-cracks with varying sizes were introduced to different graphene samples and a good agreement with the Griffith theory was found in this brittle material. Similar efforts were transferred to molybdenum disulfide (MoS2) to explore its mechanical behaviors under uniaxial tensile stress. Atomic force Microscope (AFM) was employed for friction measurements on CVD-grown single crystal MoS2 domains.
In situ tensile testing; Suspended graphene; CVD; Griffith theory; Friction measurements