TITLE:
High-Purity Amorphous Boron Synthesis from Boron Trifluoride and Lithium Hydride
AUTHORS:
Paata Nikoleishvili, Gigla Tsurtsumia, Tina Lezhava, Nana Koiava, Rusudan Kurtanidze, Nunu Jokhadze
KEYWORDS:
Hight Purity Boron, Boron Trifluoride, Borohydride Thermal Decomposition
JOURNAL NAME:
Journal of Materials Science and Chemical Engineering,
Vol.14 No.10,
October
12,
2026
ABSTRACT: Ultrapure amorphous elemental boron was prepared via a two-stage route starting from boron trifluoride diethyl etherate (BF3·Et2O) and lithium hydride. In the first stage, LiBH4 was synthesized in tetrahydrofuran at 50˚C - 55˚C using an optimized LiH:BF3 molar ratio of 4.7:1, yielding 93% isolated product at >99% 11B NMR purity, fluoride-free and with negligible diborane emission. In the second stage, the isolated LiBH4 was thermally decomposed in a horizontal tube furnace under argon at 650˚C, with thermal events consistent with decomposition via a Li2B12H12 intermediate. Staged ethanolysis and dilute acid purification yielded amorphous nanostructured boron of 98.7% purity, with primary particle size ~60 nm, specific surface area 45 m2·g−1.