Enhanced acetone sensing properties of W-doped ZnFe₂O₄ electrospinning nanofibers

Acetone not only harms the human body but is also considered a diabetes biomarker. A series of acetone-sensitive W-doped ZnFe₂O₄ composite nanofibers were successfully prepared in this study using a simple single-spinneret electrospinning method and a 600 °C calcination treatment. The crystalline phase, morphology, and elemental composition of ZnFe₂O₄ nanofibers with varying levels of W doping were systematically characterized and analyzed. The gas-sensitive sensing properties of the nanofibers were also thoroughly investigated. The results demonstrate that W is successfully doped into the ZnFe₂O₄ lattice, leading to a significant reduction in the crystallite size that composes the nanofibers and the formation of Fe₂O₃ olive-shaped nanoparticle embellishments on the surface of nanofibers. Meanwhile, the generation of heterojunctions and reduction of crystallite size significantly enhance the sensitivity and selectivity of ZnFe₂O₄ to acetone vapor. The sensors based on 6 mol% W-doped ZnFe₂O₄ composite nanofibers, in particular, exhibit a response of up to 1.95 for 0.125 ppm acetone vapor at 200 °C. Finally, a comprehensive examination of the acetone sensing mechanism of W-doped ZnFe₂O₄ is performed, as well as the potential causes for morphological changes and heterojunctions to improve the gas-sensitive performance of ZnFe₂O₄.