Pd-modified SmFeO 3 with hollow tubular structure under light shows extremely high acetone gas sensitivity

Currently, SmFeO 3 -based sensors are an effective platform for detecting acetone gas. However, they require high operating temperatures, which increases energy consumption and safety hazards, and their response is low when the gas concentration is at 10 –9 (PPB), which cannot meet the requirements of using exhaled breath to pre-diagnose diabetes. Herein, Pd–SmFeO 3 hollow nanotubes with an extremely high specific surface area and porosity were synthesized by electrospinning. After Pd doping, the specific surface area improved by more than two times, and the acetone response improved by more than three times. In addition, the response further improved by more than 1.5 times, and the optimum operating temperature reduced by 100 °C under light irradiation. Moreover, the relative humidity adaptability, long-term stability, and selectivity of the material were significantly improved after Pd doping or light irradiation. Finally, the acetone concentration in a person’s exhaled breath was detected by a Pd-SmFeO 3 -based gas sensor, and the error was less than 10% compared to that obtained by gas chromatography–mass spectrometry method. Graphical abstract