SnO2/SnS2 nanotubes for flexible roomerature NH3 gas sensors

Abstract

Complex composites have attracted tremendous attention due to their superior physic-chemical properties. In this work, using electrospun-synthesized SnO2 nanotubes as backbones, tubular SnO2/SnS2 composites were successfully prepared from an in situ hydrothermal sulfuration process. As-synthesized composite SnO2/SnS2 nanotubes have an average diameter of about 300 nm and are aggregated into numerous small nanoparticles. Flexible gas sensors were fabricated with the composite SnO2/SnS2 nanotubes on a polyethylene terephthalate (PET) substrate. When exposed to ammonia (NH3) gas at room temperature, the flexible SnO2/SnS2 nanotube sensors exhibited excellent sensitivity as high as 2.48 (100 ppm NH3), almost twice as high as pure SnO2 nanotubes. In addition, the sensors also showed a fast response time, excellent repeatability, stability and outstanding selectivity. Studies found that the hollow structures and the synergistic effect of both SnO2 and SnS2 played important roles in enhanced the sensing performance.