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arXiv · 2410.11334

Hexagonal boron nitride crystal growth in the Li3BN2-BN system

Camille Maestre·Philippe Steyer·Bérangère Toury·Catherine Journet·Vincent Garnier
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Abstract

Hexagonal boron nitride (hBN) presents valuable intrinsic properties and attracts considerable attention for the development of novel two-dimensional (2D) materials-based technologies. Even though huge efforts have been made to improve the bottom-up synthesis of integrated and high quality hBN, the devices presenting the best performances are still made using hBN exfoliated from bulk crystals. In this context, we explore the Polymer-Derived Ceramics (PDC) route coupled to a high temperature process that produces millimetric and high quality hBN crystals. By investigating the (micro)structure of several samples, we demonstrate that the crystal growth occurs by segregation from a Li3BN2-BN solution upon cooling and from hBN seeds. In particular, we show that crystallization can occur at a temperature as low as 1400{\textdegree}C. Overall, these results show that hBN crystal growth in the Li3BN2-BN system is compatible with conventional flux methods that may be the most promising platform for continuous seeded hBN crystal growth.

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Camille Maestre, Philippe Steyer, Bérangère Toury, Catherine Journet, Vincent Garnier. 2024-10-15. Hexagonal boron nitride crystal growth in the Li3BN2-BN system. https://doi.org/10.1021/acs.chemmater.4c01995

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