Research Highlights

Research Highlights

Precisely Sized Channels in Novel Electrodes Enable Electrochemical Water Desalination

Z-contrast Scanning Transmission Electron Microscopy performed at CNMS shows the “tunnel” (or “channel”) structure in stable MnO2 nanowires, which have precisely tuned sizes that give them selectivity to particular ions in brackish water.

B. W. Byles, D. A. Cullen, K. L. More, and E. Pomerantseva, "Tunnel structured manganese oxide nanowires as redox active electrodes for hybrid capacitive deionization," Nano Energy 44, 476-488 (2018). DOI: 10.1016/j.nanoen.2017.12.015

Seeing and Measuring Nanoscale Pores in Industrial Materials

Helium ion microscopy is shown to be a highly promising method to quickly determine porosity on commercial SiO2 samples commonly used for catalysis, outperforming SEM by overcoming charging effects (or requirement of sample pretreatment) and providing higher resolution as well as providing much faster and more detailed information than gas absorption methods.

M. J. Burch, A. V. Ievlev, K. Mahady, H. Hysmith, P. D. Rack, A. Belianinov, and O. S. Ovchinnikova, "Helium ion microscopy for imaging and quantifying porosity at the nanoscale," Anal. Chem. 90, 1370-1375 (2018). DOI: 10.1021/acs.analchem.7b04418

Deactivation Mechanism in NOx Reduction Zeolite Catalysts Revealed by Atom Probe Tomography

Atom-level deactivation processes in industrial zeolite catalysts are revealed in atom probe tomography (APT), which yields the first direct observations of chemical distributions.

J. E. Schmidt, R. Oord, W. Guo, J. D. Poplawsky, B. M. Weckhuysen, "Nanoscale tomography reveals the deactivation of automotive copper-exchanged zeolite catalysts," Nature Communications 8, 1666 (2017). DOI: 10.1038/s41467-017-01765-0

Discovery of a New Class of 1D Electrides with Nontrivial Band Topology

A combination of coupled first-principles calculations and database searches led to a discovery of electrides having 1D building blocks that accommodate topologically protected metallic states.

C. Park, S. W. Kim, and M. Yoon, "First-principles prediction of new electrides with nontrivial band topology based on one-dimensional building blocks," Phys. Rev. Lett. 120 (2), 026401 (2018).

Understanding the Nanoscale Behavior of Iron Anodes for Rechargeable Iron-Air Batteries

Using in-situ electrochemical atomic force microscopy, electrochemically induced surface reactions are observed at an electrolyte-anode interface, as needed for the advancement of iron-air batteries.

H. Weinrich, J. Come, H.Tempel, H. Kungl, R.-A.Eichel, N. Balke, "Understanding the nanoscale redox-behavior of iron-anodes for rechargeable iron-air batteries," Nano Energy 41, 706 (2017).  DOI: 10.1016/j.nanoen.2017.10.023

Directing Matter with Ions

Helium ions are used to fabricate highly pure platinum structures in liquid, with sizes to below 15-nanometers – smaller than by other direct-write technique.

A. V. Levlev, J. Jakowski, M. J. Burch, V. Iberi, H. Hysmith, D. C. Joy, B. G. Sumpter, A. Belianinov, R. R. Unocic, and O.S . Ovchinnikova, "Building with ions: towards direct write of platinum nanostructures using in situ liquid cell helium ion microscopy," Nanoscale 9, 12949 (2017).  DOI: 10.1039/C7NR04417H

A Predictive Model to Guide Experimental Identification of Stacking in Two-Dimensional Materials

A model forms a “road map” for using low-frequency Raman signatures to efficiently determine properties of stacked 2D materials.

L. Liang, A. A. Puretzky, B. G. Sumpter, V. Meunier, Nanoscale, accepted for publication (2017).  DOI: 10.1039/C7NR05839J

New Method to Detect Spin Current in Topological Insulators

Four probe scanning tunneling microscopy, simultaneously using ferromagnetic and nonmagnetic probes, effectively forms a “spin voltmeter.”

S. M. Hus, X.-G. Zhang, G. D. Nguyen, W. Ko, A. P. Baddorf, Y. P. Chen, A.-P. Li. Phys. Rev. Lett., 119, 137202 (2017).   DOI: 10.1103/PhyRevLett.119.137202



Accurate Method to Measure SiGe/Si/SiGe Interfacial Widths via Atom Probe Tomography

A correction that considers artificial density differences in Atom Probe Tomography data is developed; this leads to the ability to determine interfacial widths with 1 Å precision.

O. Dyck, D.N. Leonard, L.F. Edge, C.A. Jackson, E.J. Pritchett, P.W. Deelman, and J.D. Poplawsky, Adv. Mater. Interfaces, accepted for publication and available as “early view” paper (2017).  DOI: 10.1002/admi.201700622