Transforming Nanocrystals into Superhard Boron Carbide Nanostructures
Boron carbide (B<sub>4+δ</sub>C) possesses a large potential as a structural material owing to its lightness, refractory character, and outstanding mechanical properties. However, its large-scale industrialization is set back by its tendency to amorphize when subjected to an external stress. In the present work, we design a path toward nanostructured boron carbide with greatly enhanced hardness and resistance to amorphization. The reaction pathway consists of triggering an isomorphic transformation of covalent nanocrystals of Na<sub>1-<i>x</i></sub>B<sub>5-<i>x</i></sub>C<sub>1+<i>x</i></sub> (<i>x</i> = 0.18) produced in molten salts. The resulting 10 nm B<sub>4.1</sub>C nanocrystals exhibit a 4-fold decrease of size compared to previous works. Solid-state <sup>11</sup>B and <sup>13</sup>C NMR coupled to density functional theory (DFT) reveal that the boron carbide nanocrystals are made of a complex mixture of atomic configurations, which are located at the covalent structural chains between B<sub>11</sub>C icosahedral building units. These nanocrystals are combined with a spark plasma-sintering-derived method operated at high pressure. This yields full densification while maintaining the particle size. The nanoscaled grains and high density of grain boundaries provide the resulting nanostructured bodies with significantly enhanced hardness and resistance to amorphization, thus delivering a superhard material.
Authors
- Alexandre Maı̂tre (ORCID: https://orcid.org/0000-0002-4706-3741)
- David Portehault (ORCID: https://orcid.org/0000-0003-4914-4913)
- Christel Gervais (ORCID: https://orcid.org/0000-0001-7450-1738)
- Sylvie Le Floch (ORCID: https://orcid.org/0000-0001-9330-5361)
- Yann Le Godec (ORCID: https://orcid.org/0000-0002-9221-7076)
- Keevin Béneut
- Ludovic Delbes (ORCID: https://orcid.org/0000-0001-9752-9522)
- Cristina Coelho Diogo
- Olivier Beyssac (ORCID: https://orcid.org/0000-0001-8879-4762)
- Benoı̂t Baptiste (ORCID: https://orcid.org/0000-0002-3762-0663)
- Gwenaëlle Rousse (ORCID: https://orcid.org/0000-0001-8877-0015)
- Thomas Gaudisson (ORCID: https://orcid.org/0000-0003-3751-0138)
- Karsten Rasim (ORCID: https://orcid.org/0000-0003-1431-7351)
- Fernando Igoa (ORCID: https://orcid.org/0000-0002-3960-4720)
- Yuri Grin (ORCID: https://orcid.org/0000-0003-3891-9584)
- Virgile Malarewicz (ORCID: https://orcid.org/0000-0003-4836-6039)
Institutions
- Université Claude Bernard Lyon 1 (FR)
- Centre National de la Recherche Scientifique (FR)
- Max Planck Society (DE)
- Collège de France (FR)
- Sorbonne Université (FR)
- Chimie de la Matière Condensée de Paris (FR)
- Chimie du Solide et Energie (FR)
- Institut Lumière Matière (FR)
- Centre Européen de la Céramique (FR)
- Institut de minéralogie, de physique des matériaux et de cosmochimie (FR)
- Institut de Recherche sur les Céramiques (FR)
- Institut de Recherche pour le Développement (FR)
- Université de Limoges (FR)
Publication Details
- Journal
- ACS Nano
- Published
- 2024-10-25
- DOI
- https://doi.org/10.1021/acsnano.4c08599
- Citations
- 4
- Primary Topic
- Boron and Carbon Nanomaterials Research
- Type
- article
- Field-Weighted Citation Impact
- 0.47
Funders
- Ministère de l'Education Nationale, de l'Enseignement Superieur et de la Recherche
- Sorbonne Université