First-Principles Simulations Correlating X-ray Absorption Spectroscopy Features to Point Defects in h -BN

Sun, Wenyu [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States). Laboratory for Energy Applications for the Future (LEAF)] (ORCID:0000000235213327); Seo, Minsuk [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Bayu Aji, Leonardus Bimo [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Taylor, Gregory V. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Baker, Alexander A. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000307000858); Kucheyev, Sergei O. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Wan, Liwen F. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States). Laboratory for Energy Applications for the Future (LEAF)] (ORCID:0000000253910804)

doi:10.1021/acs.jpclett.5c00768

DOE OSTI · 2587127

First-Principles Simulations Correlating X-ray Absorption Spectroscopy Features to Point Defects in h -BN

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Abstract

Hexagonal boron nitride (h-BN) is a promising material for a range of emerging applications in electronics, quantum information technology, and energy storage. Soft X-ray absorption spectroscopy (XAS) is powerful to reveal atomic details of BN, especially in the presence of defects. However, correlating XAS spectral features with specific defect types remains elusive. In this Letter, we report B K-edge XAS measurements of sputter-deposited turbostratic h-BN films and use a combination of first-principles spectroscopic simulations and analysis of detailed electronic structure and local charge transfer characteristics to elucidate their unique spectroscopic features. Our results show that the two main defect-related peaks, between the main π* resonances of h-BN and B2O3, as typically observed in BN films deposited by energetic condensation or bombarded with energetic ions, are associated with electronic states of H-passivated B atoms bonded to one and two oxygen impurity atoms, respectively. These conclusions hold significant implications for applications relying on defect-mediated properties of h-BN.

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Sun, Wenyu [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States). Laboratory for Energy Applications for the Future (LEAF)] (ORCID:0000000235213327), Seo, Minsuk [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Bayu Aji, Leonardus Bimo [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Taylor, Gregory V. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Baker, Alexander A. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000307000858), Kucheyev, Sergei O. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Wan, Liwen F. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States). Laboratory for Energy Applications for the Future (LEAF)] (ORCID:0000000253910804). 2025-04-10. First-Principles Simulations Correlating X-ray Absorption Spectroscopy Features to Point Defects in h -BN. https://doi.org/10.1021/acs.jpclett.5c00768

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