Study on TiO2-SnO2 core-shell heterostructure nanofibers with different work function and its application in gas sensor

Abstract A core-shell heterostructure nanofibers (NFs) have been synthesized via a coaxial electrospinning approach. Two semiconducting metal oxides (SMOX) with different work function were selected to form the core-shell heterostructure NFs. In this work, SnO 2 and TiO 2 were chosen as the selected SMOXs for the synthesis of the core-shell heterostructure NFs. The electrons in TiO 2 will flow to SnO 2 , because the work function of TiO 2 is smaller than SnO 2 . This phenomenon could result in an increase of the electrons concentration in the SnO 2 shell layers and the amount of adsorbed oxygen species increased. Therefore, the gas sensing properties of the TiO 2 -SnO 2 core-shell heterostructure NFs were enhanced including a high response to the target gas, good selectivity to the target gas and the rapid response/recovery processes. The approach and results proposed in this study may contribute to the realization of more sensitive core-shell heterostructure NFs sensors.