Shape-modulated synthesis of mullite SmMn2O5 nanostructures with fast sensing response to acetone.

Abstract Development of semiconductor sensing materials with fast response requires low reaction barrier between gas species and materials surface, hence contributing to real-time gas monitoring. Herein, mullite SmMn 2 O 5 nanofibers (SNFs), nanotube-in-tubes (NT@NTs), and porous nanotubes (PNTs) have been achieved, via optimized electrospinning technique and annealing procedure. The formation mechanism for present shapes of SmMn 2 O 5 nanostructures was discussed. With respect to the sensing properties to acetone, three sensors prototypes employed with SmMn 2 O 5 NT@NTs, SNFs and PNTs were built and in detail studied by taking SmMn 2 O 5 SNFs sensor as an example. Delightfully, the sensor exhibited the response and recovery time as short as 3 s and 8 s at 300 °C, respectively. The intrinsic high catalytic activity of SmMn 2 O 5 lowers the sensing reaction barrier, which might contribute to the reaction kinetics thereby the fast sensing behavior. This work provides synthetic strategies towards one-dimensional (1D) mullite families and the novel material for acetone gas detection would facilitate further development of gas sensing. Graphical abstract fx1 Highlights • Mullite SmMn 2 O 5 solid nanofibers (SNFs), nanotube@tubes and porous nanotubes are firstly synthesized via electrospinning. • The unique shapes of 1D mullite SmMn 2 O 5 are tuned by optimized annealing. • The mullite sensors exhibit fast response and recovery to acetone (3 s and 8 s), for the real-time monitoring. [ABSTRACT FROM AUTHOR]