Fabrication of copper ferrite nanotubes via electrospinning and their hydrogen sulfide gas sensing performance

By precisely tailoring the calcination temperature of the electrospun polymer precursor, we succeeded in fabricating spinel-structured CuFe2O4 nanotubes that possess a well-defined nanotube architecture with outer diameters ranging from 200 to 300 nm. Compared with the mixed CuO and α-Fe2O3 phases formed at lower temperatures, these single-phase nanotubes offer significantly enhanced gas-sensing performance. Operating at an optimal working temperature of 200 °C, the CuFe2O4 nanotubes exhibit a pronounced response toward 1 ppm hydrogen sulfide (H2S), achieve an impressive detection limit as low as 100 ppb, and demonstrate excellent linearity (R2 ≈ 0.996) across the concentration range of 0.1–3 ppm. This combination of high sensitivity, low detection limit, and reliable quantification capability makes the CuFe2O4 nanotubes highly promising for real-time, trace-level H2S monitoring in environmental, industrial, and breath-analysis applications.