Room temperature flexible NH3 sensor based on polyaniline coated Rh-doped SnO2 hollow nanotubes

In this work, polyaniline (PANI) coated Rh-doped SnO2 hollow nanotubes (PRS) were synthesized via electrostatic spinning and in-situ polymerization technique. The obtained samples were characterized by X-ray diffractometer, Field emission scanning electron microscopy, Transmission electron microscopy, X-ray photoelectron spectroscopy and Brunauer-Emmett-Teller. The gas sensing performances of the sensors based on PRS nanotubes were investigated systematically at room temperature. It was shown that the polyaniline coated 0.5 mol% Rh-doped SnO2 nanotube (PRS0.5) sensor exhibited the highest response value of 13.6 to 100 ppm NH3 at room temperature with excellent selectivity, acceptable repeatability and favorable flexibility. The enhanced gas sensing performances were due to the morphology structure, the heterojunction between PANI and Rh-SnO2 and the catalytic effect of Rh2O3. Thus, the PANI coated Rh-doped SnO2 hollow nanotubes could be a promising candidate for designing and fabricating flexible NH3 gas sensor at room temperature.