Fabricating pod-like SnO2 hierarchical micro-nanostructures for enhanced acetone gas detection

Abstract

In present work, we develop an enhanced acetone gas sensor by pod-like SnO2 hierarchical micro-nanostructures materials, which are successfully controlled morphology by hydrothermal strategy with subsequent annealing modulation. Specific annealing temperatures of modulated morphology is discussed by TG data at the initial stage of stabilization. Structures and morphology of all samples are characterized using XRD, FESEM, TEM, HRTEM, BET and XPS. Comparing the gas-sensitive properties of materials with four different annealing temperatures, the results exhibit that the pod-like SnO2 materials has the best sensing performance to detect acetone gas. The response of this sensor to 100 ppm acetone vapours is ~5 times higher, and the response/recovery time is ~1/6/~1/14 times shorter than that of the unannealed SnO2 based sensor. The further comparison indicates that this strategy is the simple and facile strategies for the rational design of SnO2 semiconductor materials with enhanced gas sensitivity in the absence of noble metal modification and other doping. In addition, the possible gas-sensing mechanism of the pod-like SnO2 hierarchical micro-nanostructures sensor is also discussed at the optimal operating temperature.