Surface Functionalization of Black Phosphorus with Nitrenes: Identification of P=N Bonds Using Isotopic Labeling
Surface functionalization of two‐dimensional crystals is a key path to tuning their intrinsic physical and chemical properties. However, synthetic protocols and experimental strategies to directly probe chemical bonding in modified surfaces are scarce. Introduced here is a mild, surface‐specific protocol for the surface functionalization of few‐layer black phosphorus nanosheets using a family of photolytically generated nitrenes (RN) from the corresponding azides. By embedding spectroscopic tags in the organic backbone, a multitude of characterization techniques are employed to investigate in detail the chemical structure of the modified nanosheets, including vibrational, X‐ray photoelectron, solid state 31 P NMR, and UV‐vis spectroscopy . To directly probe the functional groups introduced on the surface, R fragments were selected such that in conjunction with vibrational spectroscopy, 15 N‐labeling experiments, and DFT methods, diagnostic P=N vibrational modes indicative of iminophosphorane units on the nanosheet surface could be conclusively identified.
This is the peer-reviewed version of the following article: Walz Mitra, Kendahl, Christine H. Chang, Michael P. Hanrahan, Jiaying Yang, Daniel Tofan, William M. Holden, Niranjan Govind, Gerald Seidler, Aaron J. Rossini, and Alexandra Velian. "Surface Functionalization of Black Phosphorus with Nitrenes: Identification of P= N Bonds Using Isotopic Labeling." Angewandte Chemie International Edition (2020), which has been published in final form at DOI: 10.1002/anie.202016033. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Posted with permission.