posted on 2023-12-22, 22:13authored bySang-Woo Jeon, Seong Chan Kang, Hayoung Choi, Hee Il Yoo, Se Youn Moon, Tae-Hwan Kim
For
the dispersion of boron nitride nanotubes (BNNTs), noncovalent
or covalent functionalization methods in a solvent with complex procedures,
including acidic treatments, are widely used. Herein, we propose a
solvent-free functionalization of BNNTs using a facile atmospheric-pressure
cold-plasma treatment method. The plasma-treated BNNTs exhibited nearly
threefold enhanced dispersibility and fourfold improved long-term
dispersion stability compared with pristine BNNTs. These remarkable
enhancements were attributed to the presence of the O atoms and OH
molecules generated in the plasma, which reacted with the BNNT surface
to form B–N–O and OH bonds. Consequently, the wettability
of the plasma-treated BNNTs was transformed to superhydrophilicity,
resulting in the exfoliation of the BNNT bundles in water. Small-angle
X-ray scattering measurements confirmed the successful exfoliation
of plasma-treated BNNTs from bundled structures in water. From an
application perspective, the atmospheric-pressure cold plasma method
offers a solvent-free, straightforward, and robust approach for BNNT
functionalization, eliminating the need for additional post-procedures
to remove residual surfactants from BNNTs.