Novel lotus root slice-like self-assembled In2O3 microspheres: Synthesis and NO2-sensing properties

Novel lotus root slice-like self-assembled hierarchical In2O3 microspheres with porous structure are fabricated successfully by a facile, template-free solvent-thermal method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) are employed to characterize their structures and morphologies. The results reveal that the as-synthesized microspheres after calcination are cubic phase In2O3 and subunits are lotus root slice-like nanosheets with porous structure benefiting enhancement of gas sensing. The sensing properties of the sensors based on the In2O3 microspheres are investigated. The sensors show fast and excellent response to NO2. We think this higher response more than that of In2O3 nanoparticles is attributed to unique hierarchical and porous structures. Furthermore, the obtained NO2 sensor has a prominent long-term stability.