Figure 7
(a) Schematic diagrams of the acetone sensing mechanisms of heterostructure α-Fe2O3/NiO nanosheet-covered fibers in the presence of air and target acetone gas. The proposed energy band structure; (b) NiO and α-Fe2O3 in air before combination and (c) α-Fe2O3/NiO heterojunction in acetone. XPS spectra for O 1 s; (d) Bare NiO nanofibers, (e) S-2 based and (f) S-3 based on α-Fe2O3/NiO nanosheet-covered fibers.
