Materials Science & Engineering

Contest Winners

Grand Prize Winner, Scientific Merit

Quasicrystal in Mg alloy

Jiashi Miao, "Quasicrystal in Mg alloy"

This is a HAADF-STEM image of Al4Mn quasicrystal phase formed in super vacuum die casting AZ91 magnesium alloy

Grand Prize Winner, Artistic Merit

stretch study

Terry Shyu, "stretch study"

This particular example demonstrates the gradual change of texture and topology stemming from the localization of mechanical instabilities, where local rotations and bending of elements occur. The material used was a 10-micron thick graphene oxide/polyvinyl alcohol composite. Periodic arrays of cuts are introduced by plasma etching.

Category I - Optical and Scanning Electron Microscopy (First - Third Place)

The Giant Hedgehog Particles

Joong Hwan Bahng, "The Giant Hedgehog Particles"

Surface roughness can have a tremendous effect on agglomeration behavior, energy transfer, mass transport, chemical and biological processes. Micro- and nano-scale dispersions represent a convenient experimental model to investigate these effects. Micro-scale colloids with nano-scale interfacial corrugation also offer a method to integrate different scales in materials science taking advantage of both the nano- and the micro-scales. However, such dispersions are rarely available with sufficient degree of control over the surface roughness. The combination of facile fabrications, diversity of available morphologies, and application of traditional methods of microscopy makes the Hedgehog particles a convenient tool to investigate surface roughness effects and corrugation-coupled processes.
Triplets, hidden light

Ryan Breneman, "Triplets, hidden light"

Optical image of surface nucleated cristobalite spherulites in amorphous silica. On left, image taken under polarized light in reflection, on right same image taken under cross-polarized light in transmission. Cross-polarized image captures the tensile stress field surrounding the spherulites, highlighting the concentrated stresses between them. Stresses arise from thermal expansion mismatch and volume change resulting from beta-alpha cristobalite transformation. Taken as part of study on the mechanical effects of the beta-alpha cristobalite transition in partially devitrified silica.
Collision

Jian Zhu, "Collision "

SEM image of the surface of a graphene aerogel made by ice templated assembly. By controlling the ice formation direction, it is possible to control the distribution of graphene direction in the aerogel. The alignment in the image can be taken advantage of to fabricate untralight and strong materials.

Category III - Simulated Microstructures as Products of Computational Materials Science (First - Third Place)

Interactions between lithium iron phosphate nanoparticles

Bernardo Orvananos, "Interactions between lithium iron phosphate nanoparticles"

Lithium iron phosphate is a battery cathode material that phase separates into a Li-rich and a Li-poor phase. It is believed that the phase separation does not occur within nanoparticles and instead they tend to become either fully lithiated or fully delithiated by exchanging Li between particles. In this image, which corresponds to the discharge of a cell, we show the Li concentration in the particles in the front, and the Li concentration in the electrolyte in the back. The color red represents a high Li concentration and blue a low Li concentration.
Psi Hexagoned

Dylan Bayerl, "Psi Hexagoned"

Here we directly visualize quantum confinement in Indium Nitride nanowires. Nanowires of 3 different diameters are shown in cross section. The middle branch is the hydrogen passivated wurtzite crystal structure. The left branch depicts the probability amplitude of the wavefunction at the top of the valence band. The right branch depicts likewise for the conduction band minimum. The isosurfaces shown contain 90% of the respective integrated wavefunction.
Porous silicon

Guangsha Shi, "Porous silicon"

It was recently found by calculation that 2D porous silicon can have better absorption than bulk silicon. This image is the wavefunction plot of electrons in 2D porous silicon at the top valence band with wave vector [0,0,0] (at Gamma point). The probability of finding those electrons was found to be higher at the position closer to the center of quantum confined areas, but much lower in the "bridges" connecting quantum confined areas. This implies that the confined areas will contribute most to the light absorption.

Category IV - Digitally Enhanced or Colorized Images of Microstructures (First - Third Place)

Lonely leaf

Anne Juggernauth, "Lonely leaf"

The image shows a thin gel film with large dome shaped asperities. False color was applied to highlight the different parts of the image with the gray showing the metal stub and the green area represents the gel film. The blue color was used to highlight the rough texture resulting from the presence of nanoparticles. Finally, the "leaf" shows the micron sized asperities caused by the addition of particles to the gel. The brighter areas indicate the internal exposed surface and internal texture of these large features and the darker colors showing the gel covered surface.
Nano Halloween Masks

Jian Zhu, "Nano Halloween Masks "

SEM image of the surface of a graphene aerogel. Challenge yourself by counting how many hidden faces you can find in the image. Due to its high surface area, graphene aerogel can be most suitable for high capacity energy storage materials.
Autumn POSS

Kevin Golovin, "Autumn POSS"

PDMS pillars were sprayed with a low surface energy molecule, a polyhedral oligomeric silsesquioxane (POSS). The structure produced is superoleophobic because it combines the low surface tension POSS with a re-entrant curvature (overhang of the "treetops"). These surfaces cause almost all liquids to repel from them, even low surface tension oils and alcohols. The facile synthesis method of micro-molding the pillars and spraying the re-entrant 'treetops' has never before been shown to produce superoleophobic surfaces that are also flexible and transparent.