Porous MoO3/SnO2 Nanoflakes with n-n Junctions for Sensing H2S

Currently, the detection of hydrogen sulfide is important due to its negative effect on environment and human health. In this paper, the porous MoO3/SnO2 nanoflakes (NFs) with n-n junctions, composed of the interconnected nanoparticles with diameter of less than 10 nm, were successfully fabricated via a facile method. In comparison to SnO2 NFs, the gas sensing properties of the porous MoO3/SnO2 NFs showed enhanced H2S sensing performance, including higher response values, lower working temperature, and relatively fast response and recovery rates. The improved H2S sensing property is attributed to existence of n-n junctions at the interface between MoO3 and SnO2, larger surface area and bigger pore volume. The strategy presented in this work opens a new way for preparation of other types of porous metal oxide semiconductors with heterostructures for high-performance gas sensor.