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DOE OSTI · 1837850

Electron diffraction radial distribution function analysis of amorphous boron carbide synthesized by ion beam irradiation and chemical vapor deposition

Ishimaru, Manabu·Nakamura, Ryusuke·Zhang, Yanwen·Weber, William J.·Peterson, George G.·Ianno, Natale J.·Nastasi, Michael
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Abstract

Amorphous boron carbide (a-BxC) networks consist of light elements, and their low atomic scattering factors makes structural analysis by x-ray diffraction difficult. Electron diffraction has an advantage of detecting the light elements, because of the strong interaction between the matter and electrons. In this work, we prepared a-BxC by ion beam technologies and plasma-enhanced chemical vapor deposition, and characterized their structures via atomic pair-distribution functions derived from electron diffraction intensity profiles. It was found that a pentagonal pyramid is the most favorable cluster in a-B4C generated by ion irradiation, while C—C homonuclear bonds were formed in the deposited a-B x C thin film. X-ray photoemission spectroscopy revealed that the a-BxC thin film possesses more carbon than B 4 C, which is responsible for the formation of the homonuclear bonds.

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36 MATERIALS SCIENCEAmorphousAtomic pair-distribution functionBoron carbideElectron diffraction

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Ishimaru, Manabu, Nakamura, Ryusuke, Zhang, Yanwen, Weber, William J., Peterson, George G., Ianno, Natale J., Nastasi, Michael. 2021-10-18. Electron diffraction radial distribution function analysis of amorphous boron carbide synthesized by ion beam irradiation and chemical vapor deposition. https://doi.org/10.1016/j.jeurceramsoc.2021.10.020

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36 MATERIALS SCIENCE↗