Study of the synthesis and Cl2 gas-sensing properties of nanometer HNO3-doped SnO2

We focused on the effects of the inorganic acid HNO3 on the gas-sensing properties of nanometer SnO2 and prepared the powders via a dissolution–pyrolysis method. Furthermore, the powders were characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectra (EDS). Several aspects were surveyed, including the calcining temperature, concentration of nitric acid and the working temperature. The results showed that the gas response of 3 wt% HNO3-doped SnO2 powders (calcined at 500 °C) to 10 ppm Cl2 reached 316.5, at the working temperature 175 °C. Compared with pure SnO2, appropriate HNO3 could increase the gas sensitivity to Cl2 gas more significantly.

Research Highlights
► We considered the influence of the common inorganic acid HNO3 on the gas-sensing property of SnO2 as a research key.
► The gas response of 3 wt% HNO3-doped SnO2 powders calcined at 500 °C to 10 ppm Cl2 reached 316.5.
► Compared with pure SnO2, appropriate HNO3 could increase the gas sensitivity to Cl2 gas more significantly.