A cataluminescence gas sensor based on mesoporous Mg-doped SnO2 structures for detection of gaseous acetone

Abstract

In this work, the fabrication of mesoporous magnesium doped tin oxide (Mg-doped SnO₂) materials with various doping levels has been achieved through a facile one pot and low cost hydrothermal method without the use of a surfactant. The structure, morphology, chemical states and specific surface area were analyzed in detail. By tuning the amount of Mg doping concentration, a series of Mg-doped SnO₂ structures with various morphologies including flower-shaped, nanopolyhedrons, nanocubes, and microcubes were successfully synthesized. It was found that the concentration of the Mg dopant has a significant effect on the crystal structure, surface area and morphology. Moreover, the 1 : 3 Mg-doped SnO₂ had a specific surface area as high as 138.6 m² g⁻¹ with a pore size of ca. 3.8 nm. The as-synthesized Mg-doped SnO₂ materials and commercial SnO₂ powders were used to fabricate cataluminescence gas sensor devices for acetone. It was noted that the CTL sensor based on 1 : 3 Mg-doped SnO₂ nanomaterials displayed excellent acetone gas sensing performances such as a fast response time (2 s)/recovery time (25 s), high sensitivity, and good repeatability and selectivity, which indicated that 1 : 3 Mg-doped SnO₂ materials would have very promising applications in high performance acetone sensors.