Biotemplates based preparation of hierarchical ZnSnO3 porous nanostructures for fast detection of formaldehyde

The synthesis of hierarchically porous nanostructures is always highly concerned by researchers. Herein, we report a simple, low-cost and green approach to obtain hierarchical ZnSnO 3 porous nanostructures by using the branches of pterocarya stenoptera, catalpa and apricot as biotemplate, respectively. The gas sensing properties of hierarchical ZnSnO 3 porous nanostructures are systematically analyzed. The results exhibit that the ZnSnO 3 based gas sensors show not only high responses and rapid response/recovery speed (2/8 s for ZnSnO 3 -1, 1/10 s for ZnSnO 3 -2 and 2/20 s for ZnSnO 3 -3) at the working temperature of 240 o C but also excellent anti-humidity properties, gas selectivity, repeatability and long-term stability. Besides, the linear relationship between the responses and the formaldehyde concentration (1–200 ppm) is observed. The excellent gas sensing performance of the ZnSnO 3 based gas sensors is mainly ascribed to the unique structural merits. The simple synthetic method in this paper also provides implications for the design and synthesis of porous MOSs .