MVC 10 Awards Gallery

“INDIUM SELENIDE PYRAMIDS AND MESAS ON EPITAXIAL GRAPHENE“

Brian Bersch, Graduate, Materials Science and Engineering

Scientific Process: An angled and false-colored scanning electron microscopy (SEM) image of layered indium selenide structures of varied morphology grown by powder vaporization on epitaxial graphene/SiC substrates. Most notably, this image epitaxial graphene/SiC substrates to 700˚C in the presence of In powder and Se pellet precursors in a horizontal tube furnace. In this image, the graphene substrate itself is atomically flat and largely covered by InSe deposition.
indium selenide sheets, or “mesas”, of uniform thickness (tan) can also be observed, indicating several location-specific growth modes. This unique and varied indium selenide “landscape” is synthesized by heating 0-1L thick (majority buffer layer) shows indium selenide “pyramids” (in purple and green) ranging from several hundred nanometers to several microns in height, composed of thousands of individual indium selenide monolayers. In addition to pyramidal-like island growt

FIRST PLACE

“GOLD NANODOT CONTACT ON EPITAXIAL MONOLAYER MOLYBDENUM DISULFIDE (MOS2)/GALLIUM NITRIDE (GAN) MIXED DIMENSIONAL HETEROSTRUCTURE“

Kehao Zhang, Graduate Student, Materials Science and Engineering

Scientific Process: Van der Waals mixed dimensional heterostructure such as MoS2 on GaN offers new opportunities to design high powder and high frequency bipolar transistors. However, the characterization of vertical transport properties
is limited by the small domain size (~1 μm) of MoS2. Here, using gold nanodots enables the electrical measurements of the vertical junction (MoS2/GaN). Based on this design, it is demonstrated that the monolayer MoS2 film (0.6nm thick) is
electrical transparent due to the interlayer tunneling, suggesting that the thickness is critical in the design of the vertical heterostructure. This work also provides a new route to probe the transport characteristics in a sub-micron scale.

SECOND PLACE

“JUST KEEP SPINNING“

Remmi Baker, Graduate Student, Materials Science and Engineering

Scientific Process: Self-propelled particles (micromotors) are being investigated as future autonomous agents for fluid mixing in Lab-on-Chip Device (LOCs) s and cargo delivery applications, such as pollution cleanup or drug delivery.
Micromotors have been restricted to simple geometries (i.e. cylinder or spheres), and as a result of limited geometries, the particles show either translational or rotational motion but not both. Being limited to only one motion produces erratic
swimming behavior not favorable for applications. However, by applying a novel 2-photon lithography technique, I can rapidly and cheaply 3-D print self-propelled micropropellers with unusual geometries capable of swimming with both
translational and rotational motion. The combination of translational and rotational motion gives rise to stable swimming behavior similar to microorganisms (e.g. bacteria). Thus, micropropellers can be used to accomplish nontrivial fluid
mixing and transport tasks at low Reynold’s Numbers for applications in LOCs and drug delivery.

THIRD PLACE

“CRYSTAL STRUCTURE OF DIAMOND-CLEAVED SAPPHIRE SUBSTRATE“

Rui Zhao, Graduate Student, Materials Science and Engineering

Scientific Process: Sapphire is not only a precious gemstone but also an outstanding substrate for two-dimensional transition metal dichalcogenides (2D-TMDs) growth. This is a Field-emission Scanning
Electron Microscopy image (FESEM) of the inner structures of sapphire substrate cleaved by Diamond Scriber. The image demonstrates its hexagonal crystal system in detail.

FIRST PLACE

“FOREST OF SILICON NANOWIRES“

Daniel Schulman, Graduate Student, Materials Science and Engineering

Scientific Process: This is a scanning electron microscope image of a “forest” of silicon nanowires thinner than the width of a human hair formed during Deep Reactive Ion Etching (DRIE). During deep reaction ion plasma etching
contaminants and particles randomly redeposit on the silicon surface. They act as a micro mask forming high aspect ratio silicon nanowires ranging from 10s to 100s of nanometers in diameter.

SECOND PLACE

“PERSIAN ESLIMI PATTERNS IN BISMUTH TELLURIDE AND
ANTIMONY TELLURIDE NANOPLATES“

Parivash Moradifar, Graduate Student, Materials Science and Engineering

Scientific Process: A false colored Transmission Electron Microscopy (TEM) micrograph acquired from areas under strain in a bismuth telluride and antimony telluride nanoplate. 

THIRD PLACE

“GALLIUM NITRIDE ICEBERG ISLANDS“

Natalie Briggs, Graduate Student, Materials Science and Engineering

Scientific Process: Gallium nitride grown on epitaxial graphene/silicon carbide substrates through vapor-phase deposition

FIRST PLACE

“A WULFF-CONSTRUCTION PLATINUM NANOPARTICLE“

James Goff, Graduate Student, Materials Science and Engineering

Scientific Process: This is a Wulff-construction platinum nanoparticle showing the electrostatic contributions due to an implicit solvent in DFT. Areas of positive potential (shown in red) are along the
edges of the nanoparticle as well as the (100) facets. There are regions of negative potential over the (111) facets of the nanoparticle. The negative potential above the (111) faces, in conjunction with surface
strain, is thought to facilitate electrocatalytic activity. Earlier studies have shown intrinsic electronic effects of nanoparticles in vacuum. This figure demonstrates how realistic environment contributions (such as
a polarizable medium) effect the energetics of such systems. In order to improve upon current electrocatalysts for applications such as fuel cells, further understanding of environment contributions provide
valuable insights. The results are in agreement with larger scale simulations in molecular dynamics and qualitative predictions about edge and face charge distributions.

SECOND PLACE

“CHARGE TRAPPING AT TI SITES IN SrTiO3’S RECONSTRUCTED
TERMINATION UNDER ELECTRIC BIAS“

Yihuang Xiong, Graduate Student, Materials Science and Engineering

Scientific Process: Oxygen-deficient, triple TiO2 terminated SrTiO3 is fully relaxed under applied voltage in continuum solvent. The excessive charge density profile indicates that the charge trapping mainly takes place
at the Ti sites in the termination, which would affect its photocatalytic activity.

THIRD PLACE

“VIEW AT THE ACETIC ACID-WATER/ZINC OXIDE INTERFACE
DURING COLD SINTERING PROCESS“

Mert Sengul, Graduate Student, Materials Science and Engineering

Scientific Process: The ReaxFF reactive force field enables us to model reactive solid-liquid interfaces at atomistic level on nanometer-sized systems. The Cold Sintering Process benefits aqueous solutions to aid the
densification of ceramics. This image demonstrates acetic acid-water-zinc acetate/zinc oxide interface under elevated pressure and temperature. The aqua isosurface represents area of zinc oxide layer recrystallized from
aqueous solution, the red isosurface represents area of evaporated solve