DFT Study of Boron Nitride Nanotubes Modified with Metal Oxide Clusters (CrO₃, MoO₃, and WO₃) as Sensing Materials for Acetone Detection

Developing excellent gas sensors for detecting acetone is quite essential in industrial production and disease detection. Herein, density functional theory (DFT) calculation is used to investigate the adsorption behavior and sensing ability of acetone on (CrO 3 ) 3, (MoO 3 ) 3, and (WO 3 ) 3 cluster-modified boron nitride nanotubes (BNNT). The results show that there is a clear linear relationship between the electronic properties and the electronegativity of metal oxides. Acetone is synergistically captured by metal oxides and BNNT, with an adsorption strength of −0.28 ((CrO 3 ) 3 /BNNT) to −1.10 eV ((WO 3 ) 3 /BNNT). The ideal recovery time (10 s for 298 K and 4 s for 998 K), obvious charge transfer (0.253 and 0.291 e ), moderate adsorption ability (−0.77 and −1.10 eV), and sensing response degree (281 and 908) reveal the potential of (MoO 3 ) 3 /BNNT and (WO 3 ) 3 /BNNT as reusable resistance-type gas sensors. Note that they also exhibit relatively high acetone selectivity in a complex environment. Meanwhile, applying a higher positive electric field has a positive effect on improving sensing performance. The significant change in the UV–vis spectrum indicates that (CrO 3 ) 3 /BNNT is a promising optical sensing material for acetone gas. This research offers insights into developing high-performance metal oxide/BNNT nanocomposite materials for detecting acetone gas.