Electrospinning synthesis, crystal structure, and ethylene glycol sensing properties of orthorhombic SmBO3 (B[dbnd]Fe, Co) perovskites

Abstract

The target of this work is to survey the consequences of various B (BFe, Co) sites of SmBO3 perovskite on crystal structure and ethylene glycol gas-sensitive properties. To this end, two samples based on SmFeO3 and SmCoO3 nanofibers with orthorhombic phase were prepared by a straightforward and efficient electrospinning technique and calcined at 700 °C. The XRD Rietveld refinements and tolerance factor (t) were implemented to research the crystal structure by the lattice parameters, size of BOB angles and t value, BET test shows that as-prepared two samples own different pore sizes, and XPS analyzes the composition and chemical state toward two samples, which indicates that more oxygen vacancies exist in SmFeO3 surface. Then, the gas-sensing performance of SmFeO3 and SmCoO3 nanofibers were compared at their optimal working temperature of 200 °C. The gas-sensing inquiries exhibit that the response of sensor based on SmFeO3 nanofiber (14.3) is almost 6.5 times higher than that of SmCoO3 (2.2) toward 100 ppm ethylene glycol. Finally, the sensing mechanisms of SmFeO3 and SmCoO3 nanofibers were also explained based on pore size, oxygen vacancy, lattice distortion and electrical conductance.