9.4: Next Generation Nano-electronics Utilizing Piezoelectricity and Piezoresistivity of 2D Materials Beyond Graphene

Two-dimensional materials beyond graphene are gaining more attention these days. An interesting category of 2D materials known as the transition metal dichalcogenides (TMDCs) had great potentials in making high-performance electronic devices for their attractive electrical properties, e.g. piezoelectricity and piezoresistivity. Quantum mechanical calculations predict outstanding piezoelectric properties for these materials. However, such properties remain to be confirmed experimentally. The objective of this proposed research program is to conduct for the first time experimental measurements of the piezoelectrical and piezoresistive properties of TMDCs. First, a protocol will be established to fabricate suitable nanostructures made of single layer suspended nanoribbons of TMDC crystals. Second, an electro-mechanical measurement platform employing both scanning force microscope (SFM) and in-situ Raman spectroscopy will be established for characterizing both piezoelectric and piezoresistive properties of the materials. Finally, the effect of defects (such as vacancies, dislocations, and impurities) on these electrical properties will be explored experimentally. The experimental results from this study will be compared with theoretical predictions using density functional theories. This validation will be extremely beneficial to future studies where accurate models are needed for novel material design, within the mateirals genome initiative, in which mechanical, electrical behaviors are coupled. Level of Effort: In each year, this project will require 0.50 summer months of the PI’s time. Additionally, in each year, this project will require 12 months of postdoctoral fellow and graduate student time.