How clean/dirty are 2D materials?
You might be familiar with graphene - an atomically-thin layer of carbon. There are other materials that fall under this category, including some that are made of two different atomic species - TMDC's. We looked at four different types of TMDC's in air and saw that the ones containing sulfur were cleaner than the ones containing selenium. We could even resolve the atomic structure of all four types in air. When looking at the dirtier samples, we needed to look between the dirt piles, but we could still find clean areas. This leads us to conclude that sulfur-containing TMDC's are probably better for use in semiconductor devices.