Low‐Temperature Synthesis of Highly Crystallized Hexagonal Boron Nitride Sheets with Li3N as Additive Agent. Issue 32 (30th September 2014)

• Record Type: Journal Article
• Authors: Yuan, Sheng; Toury, Bérangère; Benayoun, Stéphane; Chiriac, Rodica; Gombault, François; Journet, Catherine; Brioude, Arnaud
• Is Part Of: European journal of inorganic chemistry. Issue 32(2014)
• Page Start: 5507
• Page End: 5513
• Publication Date: 2014-09-30
• Subjects: Boron -- Solid‐state structures -- Ceramics -- Graphene -- Nanostructures; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201402507
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: Highly crystallized hexagonal boron nitride (h‐BN) sheets were obtained by a versatile method modifying the original synthesis by using an additive agent and, as a consequence, decreasing the temperature for the ceramization step (1200–1400 °C). This synthesis is based on the polymer‐derived ceramics (PDCs) route using liquid‐state polyborazylene (PBN) mixed with lithium nitride (Li3 N) micropowders as additive agent. We have demonstrated that incorporation of Li3 N as a crystallization promoter allows the onset of crystallization of h‐BN at lower temperatures. Consequently, a high crystallization rate can be obtained from 1000 °C for bulk boron nitride, whereas the temperature has to be 1600–1800 °C under classical conditions. A series of samples incorporating Li3 N (5 wt.‐%) and annealed at various temperatures from 600 to 1400 °C was prepared and structurally characterized by Raman spectroscopy, XRD analyis, and TEM. Well‐crystallized sheets with thicknesses of nanometers can be easily obtained by applying this method. Abstract : A versatile method based on polymer‐derived ceramics was used to prepare highly crystallized hexagonal BN sheets. Li3 N was used as a crystallization promoter to reach highly crystallized states at a lower temperature than is required for processes without an additive agent.