High Sensing Performance of n-Butanol Gas Sensor Based on Mesoporous Cu-Doped α-Fe₂O₃ Nanoparticle Materials

Abstract

Pure and Cu-doped $\alpha $ -Fe2O3 gas sensitive materials were prepared by hydrothermal reaction. X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett–Teller (BET) techniques were used to characterize and test the morphology, elemental valence and composition, and specific surface area of Cu-doped $\alpha $ -Fe2O3 gas sensitive materials. The XRD results showed that $\alpha $ -Fe2O3 gas sensitive materials had a very good crystallinity, and the antispinel structure was formed when CuCl $_{{2}}\cdot {2}$ H2O was added to the mixed precursor solution. The addition of CuCl $_{{2}}\cdot {2}$ H2O to the mixed precursor solution resulted in the formation of CuFe2O4 with an antispinel structure. By measuring and calculating the nanoparticles shown by SEM and TEM, it was found that 3 wt% Cu doping reduced the size of the particles from 64.38 to 30.05 nm when compared with pure $\alpha $ -Fe2O3. In terms of gas sensing performance, the response of $\alpha $ -Fe2O3 sensor doped with 3 wt% Cu was 94.67 at 45% relative humidity, which is about twice of the response of pure $\alpha $ -Fe2O3. The experimental results show the great potential of $\alpha $ -Fe2O3 as a low-cost and high response gas sensitive material for n-butanol detection.