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Updated: Feb 2, 2026
Spark Plasma Sintering Apparatus Used for the Formation of Strontium Titanate Bicrystals
Published on: February 9, 2017
Advanced synthesis of highly crystallized hexagonal boron nitride by coupling polymer-derived ceramics and spark
Yangdi Li1,2, Vincent Garnier1, Catherine Journet2
1Univ. Lyon, INSA-Lyon, MATEIS, UMR CNRS 5510, 7 Avenue Jean Capelle, F-69621, Villeurbanne, France.
Abstract:
Hexagonal boron nitride nanosheets (BNNSs) are promising 2D materials due to their exceptional chemical and thermal stabilities together with their electrical insulation properties. A combined synthesis method involving the polymer-derived ceramics (PDCs) route and the spark plasma sintering (SPS) process is proposed, leading to well-crystallized and pure layered h-BN crystals, prone to be exfoliated into large BNNSs. Here we focus more specifically on the influence of two key parameters of the process to be optimized: the Li3N concentration (0-10 wt%) and the SPS temperature (1200 °C-1950 °C). The presence of Li3N, added as crystal promoter in the pre-ceramic powder, significantly improves the crystallinity level of the product, as evidenced by XRD, SEM and Raman spectrometry. SPS temperature strongly modifies the size of the resulting h-BN flakes. The influence of SPS temperature on both purity and crystallinity is studied using cathodoluminescence. h-BN flakes larger than 200 μm2 (average flake area) are obtained. Few-layered BNNSs are successfully isolated, through exfoliation process.
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