IRG-I focuses on the study and development of unique structures based on the ability to harness a newly discovered nonlinear fiber fluid instability to generate regularly sized nanospheres in fibers. The main objectives are to introduce a new materials-agnostic fabrication approach for nanospheres of arbitrary geometries and dimensions, and to develop a new paradigm for fundamental fluid-dynamic studies. This new paradigm offers a highly controlled environment for the observation of fluid instabilities involving multiple fluids co-flowing in hitherto unobtainable geometries and scales.

Rational materials design and development guided by a computational framework, validated by experimental measurements

Long-term Research Goals and Intellectual Focus: The intellectual focus of IRG1 is on the assembly of nanoscale building blocks into functional, tunable materials that operate at the meso- to macroscales. The ability to organize nanoscale components rationally, precisely, and collectively into larger-scale architectures will enable limitless possibilities for creating materials that are poised for broad impact in energy security, environmental sustainability, human health, and civil infrastructure. However, there is community consensus that coupled experimental and computational tools are a critical missing link for understanding materials function and scientific discovery at the mesoscale.

Our long-term research goal is to establish a computation-driven framework for understanding, predicting, and designing how nanocomponents dynamically assemble into complex mesoscale architectures. While the proposed framework is broadly applicable to a variety of systems, we will focus our investigation on two major materials systems where predictive mesoscale assembly has strong potential to lead to revolutionary scientific and technological advances.

Polymer-grafted nanocrystals (NCs): Solid-state NCs—here, composed of metal and metal-organic frameworks (MOFs)can be synthesized into various anisotropic shapes by controlling crystallographic nucleation and growth. When grafted with polymers, NCs assemble into a rich variety of non-close-packed architectures that are phases unto themselves and exhibit unique optical and catalytic properties.

Natural and synthetic proteins: Supramolecular protein arrays can be assembled through both chemically and genetically controlled molecular-level interactions. Reversible metal coordination, disulfide bonding, and synthetic linkers minimize the burden of designing and engineering extensive protein surfaces, while enabling the construction of porous and gel-like materials that are modular, responsive to external stimuli, and retain biological function.

Magnetoelectric (ME) materials are at the frontier of materials research due to a variety of non-trivial coupling mechanisms interweaving electric and magnetic degrees of freedom. Their properties are in many aspects superior over today’s spintronic materials where the emphasis is on creating and manipulating spin-polarized (but nevertheless dissipating) electric currents. Controlling ME coupling on the nanoscale enables unprecedented possibilities to tailor functional materials and complex nanostructures, thus opening unique perspectives for novel technologies where electrically controlled magnetism offers innovative approaches for device operation.
The primary objective of this IRG is to understand magnetoelectricity in complex functional heterostructures and enable its unconventional use beyond the realm of static equilibrium and linear response. This objective will be achieved through interdisciplinary investigations of ME antiferromagnets, complex oxide thin films, ME multiferroics, and molecular-level magnetoelectrics. They will be implemented in new functional heterostructures and subject to external stimuli giving rise to responses in a hitherto unexplored parameter space. The expected research outcomes are new insights in the ME coupling and spin dynamics of magnetoelectrics, development of novel voltage-controlled ultra-low power spintronic devices, and harnessing voltage-controlled entropy changes in conceptually new materials design.

Pluperfect Nanocrystal Architectures aims to create, characterize, and control the architectures of nanocrystal-based materials that transcend the structure and function of translationally periodic nanocrystal assemblies that have dominated the research landscape to date. In creating synthetic materials, we typically aim for perfection, preparing pure and periodic materials that are easy to model and measure. However, an opportunity exists for the self- and directed-assembly of nanocrystals that break from perfection by exploiting additional degrees of design freedom that are unavailable in atomic systems. The team will explore combinations of surface chemistry and geometrical cues that trigger and direct the formation of compositional defects, aperiodicity, and heterogeneity in nanocrystal assemblies in “hard” fabricated and “soft” liquid crystal templates. Targeted imperfection will unlock a palette of configurable and reconfigurable architectures with new functions that are not possible in traditionally “perfect” assemblies. In this way we aspire to create pluperfect nanocrystal architectures, i.e., complex, beyond-perfect, or literally “more than perfect” nanocrystal assemblies, that impart novel optical and magnetic responses.

The Northwestern University Materials Research Science and Engineering Center (NU-MRSEC) advances world-class materials research, education, and outreach via active interdisciplinary collaborations within the Center and with external partners in academia, industry, national laboratories, and museums, both domestically and abroad. The intellectual merit of the NU-MRSEC resides primarily within its interdisciplinary research groups (IRGs) and seed-funded projects that promote dynamic evolution of Center research foci. IRG-1 entitled “Reconfigurable Responses in Mixed-Dimensional Heterojunctions” explores nanoelectronic materials systems that simultaneously process and store information to provide functionality exhibited by more complex biological systems such as neural networks. IRG-2 entitled “Functional Heteroanionic Materials via the Science of Synthesis” brings together experts in bulk crystal and thin-film synthesis, computational design of materials, and advanced characterization to expand a relatively unexplored class of materials with unconventional combinations of properties such as high electrical conductivity and low thermal conductivity.

Ion transport is fundamental to nearly every process involving the transfer or conversion of chemical to electrical energy. Ion-transport membranes underpin many biological systems and are crucial to a diverse array of energy-related applications including: fuel cells, electrolyzers, batteries, electrochromics, chemical separators, membrane reactors, and sensors.The vision of this interdisciplinary research group posits that, “Fundamental understanding of ionic transport in novel, nanostructured systems can drive dramatic improvement in energy conversion efficiencies.” Center research in this area emphasizes intelligent microstructural design of composite membranes with improved stability, operational range, impurity tolerance, and transport efficiency and selectivity.

Yogesh Surendranath, Assistant Professor, Department of Chemistry

Li-O₂ batteries are poised to transform the consumer electronic and electric vehicle markets because they possess a theoretical energy density of 3,213 W h/kg, three fold larger than the current state of the art. This dramatic boost in energy density is provided by the carbon-based Li-O₂ cathode, at which O₂ is reduced to Li₂O₂ upon cell discharge. However, the insoluble Li₂O₂ precipitates indiscriminately on the surface of the carbon cathode, inhibiting subsequent reduction of O₂, leading to diminished capacity, poor rate capability, and poor round-trip efficiency. These challenges could be overcome if the surfaces of carbon cathodes can be modified to discourage the indiscriminate nucleation and growth of Li₂O₂ crystallites. We hypothesize that Li₂O₂ nucleation occurs via Li+ coordination to oxidic surface functionalities including ketones, carboxylic acids, and alcohols, which are known to be prevalent on carbon surfaces. Thus, we will apply well-known oxygen protecting group (PG) chemistries (e.g. silylation, benzylation, alkylation) to carbon electrodes to impede the nucleation of Li₂O₂ crystallites. By reducing the nucleation site density, fewer, larger Li₂O₂ crystallites will be favored, leaving the majority of the electrode surface available to sustain rapid O₂ reduction, thereby, enabling high energy and power densities.

 

 

Meeting world energy needs is one of the most significant challenges we face in the coming century. The Renewable Energy Materials Research Science and Engineering Center is focused on transformative materials advances and educational directions that significantly impact the emerging renewable energy technologies.

 

 

 

The goal of this IRG is to develop new materials and new components for use in 'soft systems,' such as soft robotics, foldable motors, and muscle-like actuators.

 

The substantial and sustained investment in the sciences at NYU, the founding of NYU’s Tandon School of Engineering, and the inaugural MRSEC award in Y2008 have created a dynamic environment for interdisciplinary materials research that is on a steep upward trajectory. The second generation of the Center unites investigators from Chemistry, Physics, Chemical and Civil Engineering, the Courant Institute of Mathematical Sciences, and the NYU College of Dentistry in a program encompassing two Interdisciplinary Research Groups (IRGs), a technology-focused Seed component that capitalizes on New York’s thriving entrepreneurial culture, and a comprehensive education program that captures learners at all levels. The goals of the NYU MRSEC are straightforward – perform world-class research that cannot be performed by individual investigators alone, instill an interdisciplinary culture in graduate students and postdocs for thriving careers, and cultivate excitement in STEM among young scientists and engineers.  

The research mission of the NYU MRSEC revolves around two IRGs and Seed projects:

IRG 1: Random Organization of Disordered Materials combines researchers from Chemistry, Civil and Chemical Engineering, Mathematics and Physics to investigate new principles for organizing and controlling the microstructure of multiscale materials. The IRG builds on the remarkable discovery of the Random Organization Principle, pioneered by NYU MRSEC investigators, by which systems driven out of equilibrium evolve towards absorbing states in which dynamic rearrangement ceases. IRG 1 explores the structures and correlations that arise in granular, multicomponent and active materials under external and internal driving, particularly those of the absorbing states, seeking to optimize material properties such as yield strength and photonic band structure, and to develop active materials such as optically reconfigurable colloids and active extensile viscoelastic liquids.

IRG 2: Molecular Crystal Growth Mechanisms assembles a team from Chemical Engineering, Chemistry, Mathematics, and Physics to investigate the fundamental science of molecular crystal growth, an area of vital interest for pharmaceuticals, organic electronics, and other technologies. While crystal growth of metals, semiconductors, and binary oxides is highly developed, understanding of basic elements of molecular crystal growth is lacking. The IRG advances the understanding of essential aspects of crystal growth science and engineering, investigating nucleation, dislocation generation and structure, multi-step assembly at the unit cell level, and origins of non-classical morphologies in molecular crystals. IRG 2 combines theoretical modeling, computer simulation, and experiment to develop predictive models of crystal structure and free energy and to investigate the dynamic aspects of crystal growth.

Seeds: During Year 1, the Center made four Seed awards aimed at investments in junior faculty and at emerging proto-IRGs, including (i) Multi-Scale Biomaterials, (ii) One-Dimensional Nickel and Cobalt Wires: Synthesis and Characterization, (iii) Hyperbranched nanoparticles from Reverse Micelles, (iv) Spectroscopic measurement of site- and depth-resolved electronic structure inside battery electrodes during charge cycling.