This Northwestern University MRSEC seed project is designing and building molecules to bridge the QD-MoS2 interface, thus enabling control over this ultrafast charge transfer. These photoswitchable molecules can be rapidly toggled between two different states using different colors of light.
Recently, novel methods based on materials informatics and machine-learning models have emerged to assist the search for materials with improved properties in industrially relevant applications. To apply this approach in heteroanionic materials discovery, NU-MRSEC IRG-2 has reported a computational investigation of a series of ternary HetMs with tunable band gaps from machine-learning and crystal structure prediction.
Heteroanionic doping of metal oxide semiconductors enables unique optoelectronic properties as a result of the tunable bonding and variable charge transport properties imparted by diverse anion chemistry. Here the effects of fluoride (Fˉ) doping in an archetypical metal oxide semiconductor, indium oxide (In-O), is studied.
In a five-PI collaboration within NU-MRSEC IRG-1, photoinduced charge separation is probed between InSe and two organic molecular semiconductors using novel experimental techniques that combine laser illumination with conductive scanning probe microscopy. In addition to providing insight for mixed-dimensional InSe-organic van der Waals heterostructures, this work establishes a general experimental methodology for studying localized charge transfer at the molecular scale that is applicable to other photoactive nanoscale systems.
Most inorganic quantum dots are obtained through organic synthesis using surface ligands. When deposited on two-dimensional materials such as MoS2, such ligands form an “interlayer” between the components of the resulting mixed-dimensional heterojunction. To understand the effects of this interlayer, a collaborative theory and experimental effort in NU-MRSEC IRG-1 effort has modeled and characterized the electronic structure of CdSe nanoplatelets with well-controlled ligand-dipole terminations.
The Princeton MRSEC iSuperSeed focuses on the topics of polymeric materials driving structure and biological function at (i) the intracellular length scale, where recent observations of phase-separated liquid phases (left top image) are relevant to understanding responses inside cells, and (ii) extra-cellular length scales where porous material change shape or regulate run-and-tumble dynamics
Majorana zero modes (MZMs) can serve as building blocks for topologically protected quantum computers, promising scalable and fault-tolerant quantum computation platforms in the future. Princeton MRSEC investigators Ali Yazdani and B. Andrei Bernevig have realized a novel material platform based on the topological hinge state of bismuth.
The Wisconsin MRSEC has created thin films of a fascinating magnetic material, Pr2Ir2O7, in which the magnetic moments are frustrated: No matter how they are arranged, some of the moments are always fighting to change their direction, like two bar magnets with their north poles shoved together. Frustration creates a rich landscape for discovery and manipulation of new magnetic effects and of electronic phenomena linked to magnetism.
This year the Wisconsin MRSEC launched the first Wisconsin MRSEC Excellence in Open Science Prize. The winner was graduate student Bradley Dallin for his work on molecules interacting with water, with potential applications from understanding human blood to protein folding diseases like Alzheimer’s. Bradley shared his results in papers, but also shared all his simulations and tools in an open accessible format for the community, increasing the impact of his work.
The Zhu group developed a facile method to disassemble vdW single crystals layer by layer into monolayers with near-unity yield and with dimensions limited only by bulk crystal sizes (scheme shown on top). The macroscopic monolayers are comparable in quality to microscopic monolayers from conventional Scotch tape exfoliation.
