Reduced graphene oxide/α-Fe2O3 composite nanofibers for application in gas sensors

Abstract

Pure α-Fe2O3 nanobelts (NBs) and 0.5, 1.0, 3.0wt% reduced graphene oxide (rGO)/α-Fe2O3 composite nanofibers (NFs) have been successfully synthesized by a homotaxial electrospinning method. Various techniques were employed for the characterization of the nanostructures and morphologies of the as-obtained nanofibers. The results indicate that pure α-Fe2O3 NBs have uniform widths more than 200nm and series of rGO/α-Fe2O3 NFs have diameters approximately 100nm. In addition, the gas sensing properties of the obtained nanofibers were investigated. It is found that 1wt% rGO/α-Fe2O3 shows high response, excellent repeatability and long-term stability to 100ppm acetone at the operating temperature of 375°C. The response of 1wt% rGO/α-Fe2O3 nanofibers to 100ppm acetone is about 8.9, which is about 4.5 times higher than pure α-Fe2O3 NBs.Furthermore, the combination of rGO with α-Fe2O3 can also improve the response/recovery properties. The response and recovery times of the sensor were about 3 and 9s, respectively, which were superior to pure α-Fe2O3 NBs. Finally, we have proposed that the creation of ohmic contact, defects on the rGO nanosheets surface play significant roles in raising the sensitivity of rGO/α-Fe2O3 NFs.