Covalent functionalization of boron nitride nanotubes by radical reagents

• A novel, efficient method is introduced to covalently modify non-reactive boron nitride nanotubes (BNNT). • Broad-scope functional groups are attached to the BNNT surface. • Extensive analyses confirm high functionality, validating the success of the functionalization process. • Functionalized boron nitride nanotubes perform excellent dispersion in diverse solvents, lasting for days. • The structure of the nanotubes is preserved for further applications. Boron nitride nanotubes (BNNT) possess outstanding properties, but their utilization is limited by poor solubility and processability. Current functionalization methods to address these issues employ overly harsh reaction conditions. A milder functionalization approach is needed to unlock the full potential of BNNT for diverse applications while maintaining their excellent properties. Herein, radicals generated by the decomposition of benzoyl peroxide in presence of alkyl iodides have been used to functionalize inert nature BNNT. Confirmation of successful covalent functionalization is established using infrared spectroscopy (IR), thermal gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and transmission electron microscopy (TEM). UV–Vis was used to estimate the excellent dispersion of functionalized BNNT in comparison with pristine BNNT in the two most common solvents for polymer dissolution tetrahydrofuran (THF), and dimethylformamide (DMF). This gentle functionalization process maintains the exceptional characteristics of BNNT, while simultaneously enabling their broad application and unlocking numerous novel and promising avenues for materials innovation.