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DOE OSTI · 1735381

Boron carbide amorphous solid with tunable band gap

Tucker, Mikel·Liou, Sz-Chian·Zondode, Mobolaji·Dampare, Jesse·Joseph, Halim C.·Ndaw, Marieme Soda·Hou, Jie·Pramanik, Saroj·Du, Xiaobo·Wu, Wei·Bemley Talley, Jessye Leigh·Lisfi, Abdellah·Fan, Maohong·Pan, Yong-Le·Lan, Yucheng
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Abstract

Boron carbide B x C (x = 1/6 – 10) powders were synthesized through a microwave-assisted carbothermic reduction reaction as a potential clean energy material. Their crystallographic structures and optical properties were characterized. X-ray diffraction and electron diffraction indicated that the synthesized B x C powders were amorphous. Electron energy-loss spectroscopy demonstrated that the composition of boron and carbon was in amorphous materials, and their chemical bonding were disclosed from Raman scattering spectroscopy. Here, UV-vis absorption spectroscopy indicated that the bandgap of the bulks varied from 2.30 eV to 3.90 eV, tuned by the boron/carbon element ratio.

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36 MATERIALS SCIENCEBorideCarbideCarbothermic reactionOpticalPhotovoltaic

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Tucker, Mikel, Liou, Sz-Chian, Zondode, Mobolaji, Dampare, Jesse, Joseph, Halim C., Ndaw, Marieme Soda, Hou, Jie, Pramanik, Saroj, Du, Xiaobo, Wu, Wei, Bemley Talley, Jessye Leigh, Lisfi, Abdellah, Fan, Maohong, Pan, Yong-Le, Lan, Yucheng. 2020-11-21. Boron carbide amorphous solid with tunable band gap. https://doi.org/10.1016/j.jallcom.2020.157951

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36 MATERIALS SCIENCE↗