▎ 摘　　要

The design of reduced graphene oxide (RGO) with novel porous structure has attracted tremendous attention owing to their larger specific surface area. Herein, three-dimensional open microcells, bowl-shaped RGO were fabricated through spray drying method which employed polystyrene spheres as a sacrificial template. The bowl-shaped, open microcell-liked pores observed in the RGO network had an average diameter of approximate to 1 mu m. Subsequently, the catalytic SnO2 nanoparticles were loaded on RGO network via a simple solvothermal method (SnO2@RGO), and their gas sensing properties were investigated at room temperature (RT). In a comparison with pristine RGO network, the SnO2@RGO composite exhibited almost 4 times higher response to 400 ppm NO2 at RT and rapid recovery time. The extraordinary sensing performance can be attributed to the novel open microcell-liked porous microstructure with the SnO2 catalyst nanoparticles.