Mt. Zion on a micro scale
Due to their unique electrical properties, ceramics are invaluable in many technologies, such as gas sensors, fuel cells and batteries. However, their conductivity is much higher in the grains—the crystallites that form during the cooling of many materials—while the grain boundaries—the interfaces between crystallites— are electrically resistant and limit the material’s overall performance.
As part of his doctoral research to better understand this phenomena, George Burton PhD ’19 viewed a sample of a composite ceramic-ceramic membrane—which can separate and purify hydrogen gas from syngas and would be an energy-efficient and low-cost alternative to current methods—through a focused ion beam microscope, and something felt familiar.
“Basically, the focused ion beam microscope is a nano- machining tool that can etch very specific areas of a material and allows for lifting out minuscule pieces of your sample—in my case, typically plucking out grain boundaries of interest,” Burton explained. “One day, I was looking at my sample and noticed that the grains kind of looked like mountains. I even found one grain that looked like Mt. Zion with a tiny crack running next to the grain, which reminded me of Clear Creek.”
Inspired by the familiar landscape, Burton loaded an M into the microscope’s software, and the focused ion beam rastered over the designated area of one particular grain and sputtered away the material to form a representation of the iconic M that overlooks campus but with one key difference—Burton’s version is roughly three microns across, 30 times smaller than the width of a human hair and invisible to the naked eye.