Publications

Connecting thermoelectric performance and topological insulator behavior: Bi2Te3 and Bi2Te2Se from first principles

Journal: Physical Review Applied

Depiction of the crystal structure of Bi2Te2Se, showing the layer stacking along the rhombohedral c axis. The bracket [ indicates a single Bi2Te2Se layer with Se in the central plane. The atomic positions are taken from the relaxed structure. (hi-res image) Thermoelectric performance is of...

A novel and functional single-layer sheet of ZnSe

Journal: ACS Appl. Mater. Interfaces

Side view (a) and top view (b) of the fully relaxed ultrathin three-atom-thick ZnSe sheet. The Zn-centered tetrahedrons and the Se-apexed pyramidals are shown in gray and green, respectively. Side view (c) and top view (d) of the four-atom-thick ZnSe sheet from ref 2, which is also fully relaxed for...

Vapor-Liquid Equilibrium and Polarization Behavior of the GCP Water Model: Gaussian Charge-on-Spring versus Dipole Self-Consistent Field Approaches to Induced Polarization

Journal: J. Phys. Chem. B

We developed the Gaussian charge-on-spring (GCOS) version of the original self-consistent field implementation of the Gaussian Charge Polarizable water model and test its accuracy to represent the polarization behavior of the original model involving smeared charges and induced dipole moments. For that purpose we...

Electronic Bandgap and Edge Reconstruction in Phosphorene Materials

Journal: Nano. Lett

Atomic resolved STM image of a freshly cleaved surface of black phosphorus. (a) Topographic STM image of the sample. The setup conditions for imaging were a sample-bias voltage of 1.0 V and a tunneling current of 0.12 nA. The scan size is 18 nm × 18 nm. Atomic resolved image shows a one-dimensional...

Dynamic Charge Storage in Ionic Liquids-Filled Nanopores: Insight from a Computational Cyclic Voltammetry Study

Journal: J. Phys. Chem. Lett.

The evolution of current I normalized by scan rate s (panel a) and the average counter/co-ion densities inside the pore (panel b) during the steady-state charging/discharging cycles of a 0.78 nm-wide pore. The evolutions of normalized current and ion densities during the quasi-static charging/...

Ion transport and softening in a polymerized ionic liquid

Journal: Nanoscale

Polymerized ionic liquids (PolyILs) are promising materials for various solid state electronic applications such as dye-sensitized solar cells, lithium batteries, actuators, field-effect transistors, light emitting electrochemical cells, and electrochromic devices. However, fundamental understanding of...

Facet dependent disorder in the pristine high voltage lithium–manganese-rich composite cathode

Journal: ACS Nano

Li, green; TM, magenta; O, red), arising from the presence of TM antisites in these Li columns. (hi-res image) Defects and surface reconstructions are thought to be crucial for the long-term stability of high-voltage lithium–manganese-rich cathodes. Unfortunately, many of these defects arise only...

Binding and Diffusion of Lithium in Graphite: Quantum Monte Carlo Benchmarks and Validation of van der Waals Density Functional Methods

Journal: J. Chem. Theory Comput.

Charge density difference isosurfaces for interplanar separation of 3.528 Å of graphite (a) with and without lithium (green) computed using vdW-DF2 and (b) between vdW-DF2 and PBE. The isosurfaces are plotted at 0.001 electrons/Å3, with red positive and blue negative. The lithium locally donates charge...