Preparation of sulfur-doped PANI/TiO2 nanowires and its sensing properties to mercury

TiO2 nanowires were successfully prepared via a simple hydrothermal method and a layer of sulfurized polyaniline(PANI) was loaded onto their surface to prepare a sensor of elemental mercury at room temperature. The sulfurized PANI/TiO2 composite sensor has a high sensitivity to mercury in a range of density from 5.57 mg/m3 to 126.18 mg/m3 at room temperature. The response time and recovery time are relatively short. We also investigated the sensitivity and response time to other interfering gases, such as NO2, SO2 and NH3. And the sulfurized PANI/TiO2 composite material shows a good selectivity for element mercury. The microscopic structure of the sensor was investigated via X-ray diffraction(XRD), scanning electron microscopy(SEM) and energy dispersive X-ray analysis (EDAX). The sulfurized PANI/TiO2 composite material shows a high sensitive response, and good selectivity to element mercury, which is promising for the application in the detection of element mercury.