Honors Theses and Capstones

Date of Award

Spring 2018

Project Type

Senior Honors Thesis

College or School




Program or Major


Degree Name

Bachelor of Science

First Advisor

Shawna Hollen


Scientific interest in black phosphorus, a two-dimensional semiconducting allotrope of phosphorus, has increased in the last few years, since it was shown in 2014 to have very good properties for fieldeffect transistors. Unfortunately, practical use of the material is delayed because of its tendency to degrade into a phosphoric oxide when left in air. In this thesis I present the effects of atmospheric air and pure oxygen on the transport properties of bulk black phosphorus with and without light exposure. For continuous measurements carried out by millimeter-scale four-point probe, we see no change in the resistance of bulk samples exposed to air and oxygen, with or without light. I argue that even though we see an intensity shift in the Raman spectroscopy data, indicating oxidation of the black phosphorus samples, our measured resistances remain constant because the surface layers are nearly negligible in four-point measurements of bulk crystals. I then show an estimation for the upper bound of the number of layers affected by degradation as probed by this method, with a maximum of 900 out of 660,000 total probed layers, or about 0.1%.