Fabrication and ethanol sensing properties of hierarchical S-doped In2O3 networks

Hierarchical S-doped In2O3 networks were synthesized using a hydrothermal method with graphene oxide (GO) as a template following the annealed process. The effect of the GO on the morphology and the annealing temperature on the phase of the samples is explored. Hierarchical S-doped In2O3 networks are the network mixture of nanosheets and microspheres assembled with nanowires and nanoparticles. Hierarchical S-doped In2O3 networks annealed at 500 degrees C exhibit the highest response (Ra/Rg) of 74.4 toward 50 ppm ethanol at 180 degrees C, which is approximately 2 times higher than that of S-doped In2O3 micro pompons prepared without GO as a template. Moreover, hierarchical In2O3 networks exhibit excellent selectivity and good stability to ethanol. The excellent gas sensing properties of hierarchical In2O3 networks may be due to their unique hierarchical networks, highest specific surface area (295.23 m2/g) and S doping.