This is not paint.
These are nanoparticles!
The vivid reds, blues and greens in the photo above are a result of the different sized polystyrene nanoparticles arranged in a hexagonal structure. The image below is an enlarged version of the “Y” magnified 40,000 times using the Scanning Electron Microscope (SEM) in the Malone Engineering Center. Within my second week of summer research, I was given the opportunity to independently operate the SEM, a crazy expensive piece of scientific apparatus. At this rate, I have a feeling the SEM is soon going to become my second home!
Over the past few weeks during the summer, I’ve been working in Professor Eric Dufresne’s Soft Matter Lab. This amazing opportunity to do summer research was through a fellowship I received after completing a freshman-only course called “Perspectives on Science and Engineering”. Perspectives on Science and Engineering is a class designed to introduce freshmen to the wide scope of cutting edge research in the 800+ labs at Yale. Upon completion of the course, a research stipend of $4,200 is awarded to each student to cover living expenses during summer research in New Haven or abroad with a Yale professor
Over the next few weeks, I’ll be investigating “structural color,” a phenomenon caused by nanoscale variations in the refractive index of a medium. Think of it like this: as light passes through the periodic structure of polystyrene beads, constructive and destructive interference occur and thus only specific wavelengths of light reach the viewer. Changing the size of the nanoparticles changes the wavelength of scattered light. For example, the progression of colors in the words “YALE” is composed of particles decreasing in size from 286nm to 220nm.
I’ve enjoyed working on my own independent research project, synthesizing and characterizing particles and managing my own data and analysis. I have a meeting with Professor Dufresne every week and he often joins the lab for lunch outside in the beautiful weather. I also work closely with a graduate student, Raphael Safarti, who is like my go-to big brother in the lab for all things related to Physics, Chemistry and Lab safety. I am currently trying to coat my nanoparticles with a layer of silica and will post more exciting SEM images soon!
x40,000 Magnification of the red letter “Y”
Dried polystyrene nanoparticles of only one diameter (220nm)
The Hitachi SU-70 Scanning Electron Microscope in Malone Engineering Center