Ethanol sensing properties of hierarchical SnO2 fibers fabricated with electrospun polyvinylpyrrolidone template

• A hierarchical SnO2 fibers combined hollow and stem-branches structure were obtained.
• The hierarchical PVP template was obtained with the process of electrospinning and oxygen plasma etching.
• The diameter of branches and the gaps between them could be tuned by SnO2 film thickness.
• The sensor based on the hierarchical SnO2 fibers exhibits greatly enhanced ethanol sensitivity.

In this paper, a fabrication strategy of hierarchical SnO2 fibers with the process of electrospinning, oxygen plasma etching, sputtering and annealing is presented. The process parameters including plasma etching and sputtering time were optimized and the ethanol sensing properties were investigated. The morphologies of template fibers and hierarchical SnO2 fibers were characterized by scanning electron microscopy (SEM). The results show that the morphologies of the SnO2 fibers can be tuned via adjusting plasma etching and sputtering time. The sensor based on the SnO2 fibers exhibits enhanced ethanol sensing properties due to hierarchical structure.