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arXiv · 1502.02644

In Situ Thermal Decomposition of Exfoliated Two-Dimensional Black Phosphorus

Xiaolong Liu·Joshua D. Wood·Kan-Sheng Chen·EunKyung Cho·Mark C. Hersam
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Abstract

With a semiconducting band gap and high charge carrier mobility, two-dimensional (2D) black phosphorus (BP), often referred to as phosphorene, holds significant promise for next generation electronics and optoelectronics. However, as a 2D material, it possesses a higher surface area to volume ratio than bulk BP, suggesting that its chemical and thermal stability will be modified. Herein, an atomic-scale microscopic and spectroscopic study is performed to characterize the thermal degradation of mechanically exfoliated 2D BP. From in situ scanning/transmission electron microscopy, decomposition of 2D BP is observed to occur at ~400 {\deg}C in vacuum, in contrast to the 550 {\deg}C bulk BP sublimation temperature. This decomposition initiates via eye-shaped cracks along the [001] direction and then continues until only a thin, amorphous red phosphorous like skeleton remains. In situ electron energy loss spectroscopy, energy-dispersive X-ray spectroscopy, and energy-loss near-edge structure changes provide quantitative insight into this chemical transformation process.

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Xiaolong Liu, Joshua D. Wood, Kan-Sheng Chen, EunKyung Cho, Mark C. Hersam. 2015-02-09. In Situ Thermal Decomposition of Exfoliated Two-Dimensional Black Phosphorus. https://doi.org/10.1021/acs.jpclett.5b00043

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