Synthesis and magnetic properties of Sn1−xCoxO2 nanostructures and their application in gas sensing

Sn1−xCoxO2 (x = 0, 0.01, 0.03, 0.05, 0.07) nanostructures with different morphologies are prepared by a facile hydrothermal method. The analysis from X-ray photoelectron spectroscopy indicates that the cobalt doped in SnO2 exists as Co2+. The room-temperature ferromagnetism is observed in the powder sample of Sn1−xCoxO2 with x = 0.01. The magnetic hysteresis loop is observed at room temperature with coercivity (Hc) of 120 Oe and remanent magnetization (Mr) of 3.04 × 10−2 emu/g. UV–vis spectra reveal the red shift of the band edge absorption of SnO2 after being doped with Co. The application of Sn1−xCoxO2 nanostructures in the gas sensor for detecting ethanol and acetone reveals that the as-prepared Sn1−xCoxO2 nanourchins with x = 0.03 show a high sensitivity and short response/recovery time.