Electrospun Boron Nitride Nanotube Fabrics: Tunable Thermal Conductivity through Controlled Nanotube Orientation

Boron nitride nanotubes (BNNTs) offer significant potential for enhancing thermal properties in high‐temperature materials due to their thermal stability and anisotropic conductivity. Optimal alignment within composites is crucial, as maximum efficiency and superior thermal conductivity are achieved along the nanotube axis. However, controlling BNNT orientation remains a considerable challenge. This study presents a novel fabrication method using electrospinning to align BNNTs within fibers, followed by pyrolysis to manufacture BNNT fabrics with tunable orientations. Shear forces during electrospinning align BNNTs along the fiber axis, enhancing directional thermal conductivity. The aligned BNNT fabrics show significantly higher thermal conductivity along the alignment direction than the transverse direction, confirming the effectiveness of electrospinning in BNNT alignment. This study highlights the potential of electrospinning as a method for fabricating BNNT‐based materials with tunable thermal properties. However, future research must address challenges such as increasing density, reducing porosity, and improving fiber connectivity to leverage BNNTs’ theoretical thermal conductivity. These findings contribute to developing advanced thermal management materials and the importance of optimizing nanotube orientation and connectivity for enhanced thermal performance.