Enhancement of the acetone sensing capabilities to ppb detection level by Fe-doped three-dimensional SnO2 hierarchical microstructures fabricated via a hydrothermal method

Acetone detection at the parts-per-billion (ppb) level is achieved in this work using selective and optimized Fe doping of the three-dimensional (3D) flower-like SnO 2 hierarchical microstructures. These structures were successfully synthesized via a one-step hydrothermal route. Detailed information about the crystal structure, surface morphology and composition of the Fe-doped SnO 2 microstructures was investigated using X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) techniques. Gas sensing experiments were conducted on the as-prepared Fe-doped SnO 2 sensors. The measured results show that the incorporation of Fe into the SnO 2 structure can greatly enhance the gas sensing properties of SnO 2 sensors under the optimum working temperature (200 °C). Specifically, the 1.0 mol% Fe-doped SnO 2 microstructures exhibit the highest response, fast response/recovery time, lowest detection limit and good selectivity and long-term stability. The results demonstrate that the developed Fe-doped SnO 2 gas sensor has great potential for ppb -level acetone detection in many practical applications.