Recent Progress on Stability and Passivation of Black Phosphorus

• Published in: Advanced materials (Weinheim) Vol. 30; no. 29; pp. e1704749 - n/a
• Main Authors: Abate, Yohannes, Akinwande, Deji, Gamage, Sampath, Wang, Han, Snure, Michael, Poudel, Nirakar, Cronin, Stephen B.
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 19.07.2018; Wiley Blackwell (John Wiley & Sons)
• Subjects: 2D materials; Anisotropy; black phosphorus; Degradation; layered materials; Materials science; Optical properties; Organic chemistry; passivation; Passivity; Phonons; Phosphorus; Plasmons; Surface properties; Surface stability; Vibrational states; passivation; degradation; black phosphorus; layered materials; 2D materials
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.201704749

From a fundamental science perspective, black phosphorus (BP) is a canonical example of a material that possesses fascinating surface and electronic properties. It has extraordinary in‐plane anisotropic electrical, optical, and vibrational states, as well as a tunable band gap. However, instability of the surface due to chemical degradation in ambient conditions remains a major impediment to its prospective applications. Early studies were limited by the degradation of black phosphorous surfaces in air. Recently, several robust strategies have been developed to mitigate these issues, and these novel developments can potentially allow researchers to exploit the extraordinary properties of this material and devices made out of it. Here, the fundamental chemistry of BP degradation and the tremendous progress made to address this issue are extensively reviewed. Device performances of encapsulated BP are also compared with nonencapsulated BP. In addition, BP possesses sensitive anisotropic photophysical surface properties such as excitons, surface plasmons/phonons, and topologically protected and Dirac semi‐metallic surface states. Ambient degradation as well as any passivation method used to protect the surface could affect the intrinsic surface properties of BP. These properties and the extent of their modifications by both the degradation and passivation are reviewed. Recent developments of black phosphorus (BP) surface passivation and the effect of different passivation techniques on the surface stability and device performance are highlighted. These developments are focused on understanding and controlling the fundamental chemistry of BP degradation for fabricating BP‐based devices with improved performance as well as exotic fundamental science explorations.