CAREER: Rational Synthesis of Epitaxial 2D Heterostructures

NON-TECHNICAL SUMMARY As computing systems continue to grow in scale and complexity, there is increasing interest in materials that exhibit new properties and enable improved performance. Atomically thin semiconductors, which are only a few atoms thick, exhibit properties that differ from conventional bulk materials. These thin materials provide new opportunities to tailor properties for electronic and optical technologies at extremely small thicknesses. This project is exploring new approaches to create atomically thin materials so that different regions can have distinct electronic properties at very small length scales. By studying how these materials form and how their structure influences their behavior, this research is establishing design principles for materials applicable to electronic and optical technologies. This project is also integrating education efforts that provide research and training opportunities for undergraduate and graduate students while also engaging K-12 students and teachers through hands-on learning activities. These efforts are supporting STEM workforce development and enhancing public scientific literacy and engagement with science and technology. TECHNICAL SUMMARY Two-dimensional transition metal dichalcogenides provide a platform for engineering materials with spatially varying composition and properties through epitaxial heterostructures. In these systems, interface formation, strain, and energetics differ from those in conventional thin films. This project is investigating how thermodynamic and kinetic factors govern the formation of epitaxial interfaces with controlled composition and structure at nanometer length scales. This work is also combining synthesis with a range of structural and property characterization techniques to establish relationships between synthesis, structure, and resulting properties. These efforts are complemented by analysis and modeling efforts that are guiding material design. Ultimately, this work is developing general principles for the rational design of low-dimensional epitaxial heterostructures with tailored functionality. This project is also integrating research findings into undergraduate and graduate curricula and engaging K-12 students and educators through workshops and public demonstrations, supporting participation in science and engineering. By advancing fundamental knowledge in materials science and contributing to education and STEM workforce development, this project is further enhancing public engagement with science and technology. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2543818 | Program: 01002930DB NSF RESEARCH & RELATED ACTIVIT,01002627DB NSF RESEARCH & RELATED ACTIVIT,01003031DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Saien Xie | Institution: Princeton University, PRINCETON, NJ | Award Amount: $522,322 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2543818 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2543818.html