Excellent toluene sensing properties of SnO2-Fe2O3 interconnected nanotubes.

SnO2-Fe2O3 interconnected nanotubes were obtained by combining the single nozzle electrospinning and thermal treatment methods. The results of scanning electron microscopy revealed the special structure of ruptures and interconnected nanotubes in the as-prepared materials. The toluene sensing test results of SnO2-Fe2O3 interconnected nanotubes show that SnO2-Fe2O3 interconnected nanotubes possess excellent toluene gas-sensing properties. The sensitivity of detecting limit (50 ppb) is 2.0 at the optimum operating temperature of 260 °C. The response and recovery times to 1 ppm toluene are about 5 and 11 s, respectively. Moreover, the SnO2-Fe2O3 interconnected nanotube gas sensors exhibit the remarkable selectivity to toluene, and good long-term stability.