POS4-0672
Alcohol-Triggered Interfacial Assembly of BNNTs for Simultaneous Film Formation, Alignment, and Purification
Topic
S4. Colloids, Interfaces, and Molecular Assemblies for Functional Soft Materials
When and Where
Sep 29, 2026
08:30 - 09:30
Room 301 (Grand Ballroom)
Session Chairs
Hae Jung SON
Boseok KANG
Presenter(s)
Yujin Kim (Ulsan National Institute of Science and Technology)
Co-Author(s)
Abstract
Boron nitride nanotubes (BNNTs) are promising one-dimensional (1D) nanomaterials for thin-film applications owing to their high thermal conductivity, electrical insulation, and mechanical robustness. However, uniform BNNT film fabrication remains challenging because of strong van der Waals interactions, poor dispersibility, and non-tubular impurities. Here, we present an alcohol-assisted liquid–liquid interfacial self-assembly strategy to produce two-dimensional (2D) BNNT films from a DBSA-stabilized aqueous dispersion. Ethanol addition to the DBSA-stabilized BNNT aqueous dispersion/n-hexane biphasic system alters the solvent environment, inducing partial DBSA desorption from the BNNT surface. This change modulates BNNT wettability, driving partially exposed BNNTs to the water/hexane interface, where they assemble into a transferable 2D film.
Morphological analyses show that this interfacial process yields preferentially aligned BNNT films with reduced impurity levels. Ethanol-induced DBSA desorption selectively activates dispersed BN species for interfacial trapping at the water/hexane interface. Owing to their 1D tubular geometry, BNNTs can adopt a more favorable interfacial configuration than non-tubular h-BN impurities, leading to selective interfacial trapping. Marangoni flow during ethanol addition further promotes rapid BNNT migration and contributes to initial flow-assisted alignment. Once confined at the 2D interface, the nanotubes rearrange into a lower-free-energy configuration, forming a densely packed and aligned BNNT film.
Overall, this study demonstrates a facile route for assembling BNNTs into aligned 2D films while simultaneously achieving structural purification. The proposed strategy provides a platform for BNNT-based thermal management layers, insulating dielectric composites, and functional nanomaterials.
Morphological analyses show that this interfacial process yields preferentially aligned BNNT films with reduced impurity levels. Ethanol-induced DBSA desorption selectively activates dispersed BN species for interfacial trapping at the water/hexane interface. Owing to their 1D tubular geometry, BNNTs can adopt a more favorable interfacial configuration than non-tubular h-BN impurities, leading to selective interfacial trapping. Marangoni flow during ethanol addition further promotes rapid BNNT migration and contributes to initial flow-assisted alignment. Once confined at the 2D interface, the nanotubes rearrange into a lower-free-energy configuration, forming a densely packed and aligned BNNT film.
Overall, this study demonstrates a facile route for assembling BNNTs into aligned 2D films while simultaneously achieving structural purification. The proposed strategy provides a platform for BNNT-based thermal management layers, insulating dielectric composites, and functional nanomaterials.
