Contest Winners

Grand Prize Winner, Scientific Merit

Alejandro Perez-Bergquist, "Germanium Nanofibers or Jellyfish Tentacles?" HAADF STEM image of Ge nanofibers formed by high energy ion irradiation of crystalline Ge. These fibers form by a self-formation process involving the formation and diffusion of atomic vacancies. The study of these fibers helps us better understand ion irradiation effects in materials.

Grand Prize Winner, Artistic Merit

Laura Ligeski, "Secondary Grains of Sintered Barium Titanate" This image is of the surface of a 99.6% pure barium titanate pellet that was sintered in a cold furnance at a temperature of 1300°C for two hours. This image was taken in order to study the difference between primary and secondary grain growth in this material. The faceting of the secondary grains, which was due to anisotropy of solid-vapor surface energy, can be seen in the secondary grains as multicolored stripes. This image also shows that the sintering of the barium titanate was successful because the material has almost all secondary grains with very minimal primary grains.

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

	Damien Stonick, "CdTe Quantum Dot UV Light Luminescence" CdTe colloidal, pyramidal quantum dots are observed under 40x using a UV light source. Two levels of focus were achievable, 1) the physical aggregations of the drop casting, 2) the luminescence of the aggregations. The green luminescence is characteristic of the excitations of the 2nm diameter quantum dots in the solution. The areas of higher concentration have a higher level of luminescence than the areas of lower concentration. The higher areas of concentration also have a more noticeable red shift in the luminescence. This is due either to FRET, as the solution has a dot diameter variation of 0.29nm and the higher concentration provides a higher probability of smaller dot excitations of larger dots –resulting in a red shifted wavelength of emitted light, or the Solvatochromic effect from the polar thioglycolic acid in the solution that acts as a buffer. The strong photoluminescence of the sample indicates possible photovoltaic application.
	Richard R. Lunt, "Sand in the Stars" This image of a N,N’-diphenyl-N,N’-bis(1-naphthyl)-1,1’biphenyl-4,4’’diamine (-NPD) film was taken using an optical microscope with cross-polarizers and a Nomarski filter at 20x magnification (vertical scale of the image is 1.7mm). The variations in color stem from the anisotropic indices of refraction in combination with the rotation of the crystallites with respect to the polarizer configuration. The image highlights important impacts of the growth rate on the nucleation rate and morphology of melt-grown organic semiconductors. It is also emphasizes the high degree of anisotropy common in molecular crystal structures. Such films are currently being investigated for use in organic electronic architectures.
	Qiaona/Joanna Hu, "Quartz Vaterite" Calcium-carbonate containing solution was prepared by mixing equal amounts 0.002 mol/L of reagent grade NaHCO3 and CaCl2 .2H2O into distilled deionized water (DDW), subsequently acidified by using HCl to adjust the initial pH to 3.4, under which condition the salt solution was undersaturated. Then the pH of the salt solution was increased by diffusing NH3 gas into the solution gradually. The CaCO3 crystals would precipitate when the solution reached the super saturated status with respective to CaCO3. If the diffusion rate of ammonia was high enough at around 0.134g/liter/hour, vaterite, the most unstable polymorph of CaCO3, was the dominant polymorph. Image “vaterite” was taken by Hitachi S3200N SEM at 17 kv after 24 hours, exhibiting the beautiful individual grown vaterite crystals that like 6-petal flowers, illustrating the hexagonal symmetry of vaterite.