This project will research an approach for assembling electronics-grade, continuous films of two-dimensional layered materials from nanoplates suspended in liquids. Such a process promises to dramatically reduce the cost of producing such films and the devices that are produced from them. The method has the potential to produce materials with good control of chemical composition, structure and dimensions for applications in electronics, optoelectronics, bioelectronics, energy conversion and energy storage. The proposed research program will be closely integrated with education and outreach activities. Students from underrepresented groups will be actively recruited to broaden their participation in engineering research and the research results will be integrated into graduate and undergraduate courses to further broaden educational opportunities. Together, these efforts will contribute significantly to education and training of the next generation of individuals ready to meet the challenges of the new century, including maintaining a competitive advantage for US technology.
Two-dimensional layered materials (2DLMs) are emerging as a unique class of materials setting the stage for new breakthroughs in fundamental materials science and entirely new technologies. To fully explore their potential requires scalable production of 2DLMs, ideally with relatively simple, low cost approaches. A solution chemical pathway to the scalable synthesis and assembly of 2DLM nanoplates is proposed as a new material platform for electronic, catalytic and energy applications. In particular, a molecular evolution approach will be used to identify and design specific molecular regulating agents for the solution synthesis of 2DLM nanoplates with deterministic control of all material parameters, including chemical composition, physical dimension and electronic properties. In-situ transmission electron microscopy and in-situ atomic force microscopy will be used to visualize and understand the nucleation and growth kinetics for fine control of 2D crystal formation at the atomic level. Systematic investigations will be conducted to probe the fundamental electronic properties of the 2DLM nanoplates and explore new physics originating at the interfaces in 2DLM heterostructures. Large-area assembly of 2DLM nanoplate thin films, lateral epitaxial growth to reduce or eliminate the grain boundaries, and design of new device architectures for the creation of a new generation of highly flexible electronic and optoelectronic devices will be explored. Lastly, the resulting 2DLM nanoplates will be investigated for potential applications as electrocatalysts or photocatalysts, or in energy storage applications. A fundamental understanding of the nucleation and growth mechanisms will enable the development of powerful synthetic strategies for scalable production of 2DLMs with deterministic control of all material parameters, creating a robust material system for fundamental investigation of low-dimensional physics and chemistry at the limit of single atomic thickness. The effort will establish the critical intellectual underpinnings for a new material platform of 2DLMs to enable transformative advances in diverse technologies including electronics, optoelectronics, catalysis, and energy conversion and storage.
