Tb2O3/SnO2 composite nanofibers by electrospinning for enhanced acetone sensing performance

Gas-sensing performance can be markedly enhanced by constructing metal-oxide semiconductor nanocomposites. In this study, Tb 2 O 3 /SnO 2 composite nanofibers with varying Tb 2 O 3 concentrations were synthesized via a straightforward electrospinning method followed by annealing. The heterostructure of Tb 2 O 3 /SnO 2 composite nanofibers was thoroughly characterized using techniques such as XRD, SEM, TEM, UV-Vis, and XPS. Gas-sensing properties were evaluated using a static gas testing system. The results demonstrate that the sensor with 1 mol% Tb exhibits excellent acetone sensing performance at 320 °C, showing a response value of 63.7–100 ppm acetone—two times higher than that of pure SnO 2 sensors. Moreover, it maintains a response level under high humidity comparable to that of pure SnO 2 under low humidity, although all sensors show a noticeable decrease in performance under elevated humidity. The sensor also exhibits good selectivity and a sub-ppm detection limit of 0.2 ppm, highlighting its potential for non-invasive diabetes monitoring through exhaled-breath analysis. • Tb 2 O 3 /SnO 2 nanofibers possess denser surface-active sites than pristine SnO 2 . • 1% Tb boosts acetone response to 63.7 (100 ppm, 320 °C), 2 × higher than pure SnO 2 . • Interfacial p–n heterojunction governs temperature-dependent electrical conduction. • Tb-driven oxygen spillover accelerates acetone adsorption and surface redox kinetics.