Send to

Choose Destination
Nat Mater. 2015 Aug;14(8):826-32. doi: 10.1038/nmat4299. Epub 2015 May 25.

Photooxidation and quantum confinement effects in exfoliated black phosphorus.

Author information

Regroupement Québécois sur les Matériaux de Pointe (RQMP) and Département de physique, Université de Montréal, Montréal, Québec H3C 3J7, Canada.
RQMP and Département de chimie, Université de Montréal, Montréal, Québec H3C 3J7, Canada.
Laboratoire d'Etude des Microstructures, UMR 104 CNRS-Onera, Châtillon, France.
RQMP and Département de génie physique, Polytechnique Montréal, Montréal, Québec H3C 3A7, Canada.


Thin layers of black phosphorus have recently raised interest owing to their two-dimensional (2D) semiconducting properties, such as tunable direct bandgap and high carrier mobilities. This lamellar crystal of phosphorus atoms can be exfoliated down to monolayer 2D-phosphane (also called phosphorene) using procedures similar to those used for graphene. Probing the properties has, however, been challenged by a fast degradation of the thinnest layers on exposure to ambient conditions. Herein, we investigate this chemistry using in situ Raman and transmission electron spectroscopies. The results highlight a thickness-dependent photoassisted oxidation reaction with oxygen dissolved in adsorbed water. The oxidation kinetics is consistent with a phenomenological model involving electron transfer and quantum confinement as key parameters. A procedure carried out in a glove box is used to prepare mono-, bi- and multilayer 2D-phosphane in their pristine states for further studies on the effect of layer thickness on the Raman modes. Controlled experiments in ambient conditions are shown to lower the A(g)(1)/A(g)(2) intensity ratio for ultrathin layers, a signature of oxidation.


Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center