The IRG research projects are augmented by seed projects in materials research. At present there are four seed projects in the CCMR funded through a combination of NSF and Cornell University resources.
Topological superconductivity in single layer transition metal dichalcogenides
Debdeep Jena (MatSci), Eun-Ah Kim (Phys), Katja Nowack (Phys), and Grace Xing (MatSci)
The search for a topological superconductor is one of the most exciting frontiers in superconductivity today. Topological superconductivity may enable fault-tolerant quantum information processing and give us access to fundamentally new physical phenomena. Several material systems have been theoretically proposed to host topological superconductivity. This seed focuses on a relatively simple material system in that it consists of only a single atomic layer: Hole-doped single layer transition metal dichalcogenides (TMDs) were recently identified by one of the PIs as a promising candidate. The prediction is based on the known special spin structure of the valence band of single layer TMDs and the recent observations of superconductivity in electron-doped single layer TMDs. The seed will employ ionic liquid gating of these layers to induce the required carrier density and use low-temperature electrical transport measurements as well as magnetic imaging to search for superconductivity and establish its unconventional character.
Novel Materials and Platforms for Next Generation Electrical Energy Storage Technologies
Héctor Abruña (Chem), Tomás Arias (Phys), and Brett Fors (Chem)
This Seed seeks to develop the tools needed for the computational design, synthesis and characterization of organic-based redox-active materials capable of multiple electron transfers at high potentials for next-generation electrical energy storage applications (e.g., batteries and supercapacitors). By utilizing deliberatively architected scaffold materials, this Seed will combine the double-layer (charge-separation) capacitive storage of the underlying conducting material with the pseudo-capacitive (Faradaic) storage of redox-active molecules. This will enable the design and development of electrical energy storage platforms with capacities approaching those of batteries, but with the far higher power densities typical of capacitors.
Elucidating Crystal Nucleation and Growth Mechanisms in Mixed-Cation Lead Halide Perovskites
Lara A. Estroff (MatSci), Paulette Clancy (ChemE), and Peter I. Frazier (OperRes)
Dramatic increases in solar cell efficiencies reported for hybrid organic-inorganic perovskites (HOIPs), e.g., CH3NH3PbI3, have energized the photovoltaic community’s efforts to create low-cost solar cells from inexpensive and abundant constituents. Despite their meteoric rise, fundamental questions related to their nucleation, growth, and degradation mechanisms remain unanswered, and the relationship between these processes and performance is poorly understood. Elucidating the nucleation and growth mechanisms of these materials is the central goal of this Seed, which will ultimately lead to improved device performance via tailoring crystal growth conditions. We will tackle this question through combined expertise in Bayesian search methods for accelerating materials design, computational approaches for modeling assembly in mixed organic-inorganic systems, and in situ techniques for elucidating solution-based crystal growth mechanisms. This Seed will demonstrate the combined impact of in situ growth experiments and Bayesian optimization approaches to tame the combinatorial complexity of materials discovery in HOIPs.