Synthesis of Tb2O3/ZnO composite nanofibers via electrospinning as chemiresistive gas sensor for detecting NO gas

Forming nanocomposites among different metal oxide species may lead to gas sensors with superior gas sensing properties. In this work, terbium oxide (Tb2O3) was used to form composite nanofibers with zinc oxide (ZnO) to detect nitric oxide (NO) gas. The Tb2O3/ZnO composite nanofibers were synthesized through a facile electrospinning and annealing treatment. The heterostructure was investigated by various techniques such as XRD, SEM, TEM, and XPS, whereas the gas sensing performance of the composite nanofibers was investigated with a static gas testing system. Results showed that the Tb2O3/ZnO composite nanofiber exhibited excellent sensing performance to NO at 180 °C. Specifically, the composite nanofiber with [Tb]/[Zn] molar ratio of 0.01 had a high response of 28.3 (resistance ratio) to 1 ppm NO gas at 180 °C, with low response to other interference gases. The sensor also exhibited good repeatability and long-term stability. These remarkable sensing properties indicate that conventional ZnO is still promising for real applications via material composition and structure.