Physical Properties of Materials: Exotic Physical Properties of Electronically Coupled Two-Dimensional Metal-Organic Frameworks
Abstract
This work proposed here aims to investigate the fundamental physical properties of a novel class of two-dimensional materials within the larger family of metal-organic frameworks. The latter are crystalline materials made by self-assembly through the connection of metal ions or clusters and organic ligands. Although widely researched in the context of gas storage, separation, or catalysis due to their open, porous structures, these types of materials are rarely explored in the context of electronic, optical, or magnetic applications because they generally lack strong coupling between the molecular components, be it the metal nodes, or the organic ligands. Recently, a subclass of these materials crystallizing in two-dimensional layers have shown excellent charge transport properties, suggesting strong delocalization of electrons (and holes) across the two-dimensional lattice. These materials are therefore analogous to traditional two-dimensional materials such as graphene. Unlike the latter, MOFs have confer an extremely diverse chemical composition, which in principle allows for tuning of the band structure/symmetry, the electronic levels, and Fermi energy through controlled chemical doping or chemical substitution techniques. Although several theoretical accounts focusing on two-dimensional MOFs suggest that these may show exotic physical states such as topological insulator behavior and flat band ferromagnetism, experimental investigations in the physical properties of these new 2D materials remain scarce to non-existent. Motivated by previous experimental results and a host of promising theoretical investigations, this proposal aims to synthesize new 2D MOFs and to probe the hypothesis of their behaving as 2D Dirac semimetals, topological insulators, topological crystalline insulators, superconductors, and bulk permanent (porous) magnets either by themselves or when coupled in van der Waals heterostructures with traditional 2D materials such as graphene and boron nitride. In devising new materials, significant effort will be expended to understanding and controlling the nucleation and growth of 2D MOFs, the growth and isolation of high-quality single crystals/films of these materials being key for enabling the validation of theoretical assumption and hypotheses. Graduate student researchers engaged in this work will be exposed to a wide range of synthetic and physical characterization techniques, allowing them to develop a well-rounded education motivated by fundamental inquiry of use to any problem-solving situation in the workforce. Enabling the potential discovery of new magnetic, spintronic, or superconducting materials the proposed work carries obvious importance for the Army, with potential implications in computation, data storage, magnetic sensing of analytes of interest, and energy efficiency considerations.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Oct 16, 2018
- Source ID
- W911NF1710174
Entities
People
- Mircea Dincă
Organizations
- Army Contracting Command
- Massachusetts Institute of Technology
- United States Army