Construction of Co₃O₄/SnO₂ yolk-shell nanofibers for acetone gas detection

In this work, Co₃O₄/SnO₂ heterojunctions were proposed and fabricated by single-nozzle electrospinning. Interestingly, novel yolk-shell nanofibers could be formed in a proper doped content of Co₃O₄. The gas sensing properties of sensors based on Co₃O₄/SnO₂ yolk-shell nanofibers were evaluated, and a superior response of ∼216–100 ppm acetone at 350 °C was obtained. Additionally, Our sensors have an ultrafast response time of ∼0.62 s, demonstrating remarkable selectivity for acetone and excellent stability for both humidity and long-term use. These exceptional performances are attributed to the synergistic effect of nano-heterojunctions that enhance the effective interfacial area, as well as the unique yolk-shell structure of SnO₂/Co₃O₄, which increases gas transport channels. Our results demonstrate that constructing Co₃O₄/SnO₂ yolk-shell nanofibers is an effective strategy for achieving high-performance acetone gas detection.