Controlled ultrasonication for covalent functionalization of boron nitride nanotubes

BNNTs are rapidly becoming some of the most critical nanomaterials for various potential applications. One of the biggest BNNT challenges is concerning integration into systems, which is highly dependent on interfacial compatibility. In this study, BNNTs are functionalized with 1H,1H,2H,2H-Perfluorooctan-1-ol using sonochemical assisted covalent functionalization. Addition of 1H,1H,2H,2H-Perfluorooctan-1-ol to BNNT occurs by sonolysis of the primary alcohol to form radicals that can covalently attach to the electron-deficient boron atoms of BNNTs. Experimental factors associated with applied power ultrasound, acoustic power, and total energy applied were controlled, and output responses such as Raman analysis and fluorine atomic percent were measured using XPS and EDS. Fluorine atomic percent was shown to increase with increasing power as PFO was covalently bound to the BNNTs, but unintuitively shows little response to increased total energy applied. HNMR was used to confirm loss of the hydroxyl proton after covalent attachment of PFO to the BNNTs. Graphical abstract: [Figure not available: see fulltext.].