Mechanism for acetone sensing property of Pd-loaded SnO2 nanofibers prepared by electrospinning: Fermi-level effects

Undoped and Pd-loaded SnO2 nanofibers with various Pd loading concentrations from 1.0 to 2.0 mol% had been synthesized by electrospinning with appropriate annealing process subsequently. The morphologies and nanocrystalline structures of the nanofibers were characterized by thermogravimetric analysis-differential scanning calorimetry, X-ray diffraction, Fourier transform infrared, energy dispersive X-ray spectroscopy, scanning electron microscopy, transmission electron microscopy, and N-2 physical adsorption. The sensing properties of undoped and Pd-loaded SnO2 nanofibers were compared. The gas sensing results showed that 1.5 mol% Pd-loaded SnO2 nanofibers got a best response to acetone at lower operating temperature of 275 A degrees C among all the Pd-loaded SnO2 nanofibers. The enhanced acetone response of Pd-loaded SnO2 nanofibers may be correlated with the Fermi-level effects of Pd catalysts.