Assessment of boron nitride nanotube materials using X-ray photoelectron spectroscopy

Abstract

With increasing prevalence of boron nitride nanotubes (BNNTs), the need for routine and reliable assessment methods is becoming more critical both for research studies and for quality control in nanotube manufacturing. The assessment of BNNT materials using X-ray photoelectron spectroscopy (XPS) is described here through analysis of raw-BNNT materials and three case studies showing modification of BNNTs by purification or chemical functionalization. Metrics indicative of the BN content of the material, with the simplest being the B:N ratio, are described and tracked to show evolution of BNNT materials during processing. Along with changes in the elemental composition and the content of BN, high-resolution spectra of the B 1s region also show clear evolution as BNNT materials are modified, which can be used as a measure of boron nitride content and quality to assess BNNT production, purification, and functionalization.