Morphology-controlled porous α-Fe2O3/SnO2 nanorods with uniform surface heterostructures and their enhanced acetone gas-sensing properties

Abstract

Morphology-controlled porous α-Fe2O3/SnO2 nanorods with uniform surface heterostructures have been fabricated by a facile surface modification of rod-like α-Fe2O3 nanomaterials by changing the adding amount of Sn composition, displaying the excellent selectivity and sensitivity of gas-sensing to acetone. The introduction of SnO2 nanoparticles had the great effects on tuning the crystal size, crystallinity, and surface status, as well as the structural stability and phase distribution of α-Fe2O3/SnO2 nanorods. Compared to pure α-Fe2O3, α-Fe2O3/SnO2 heterostructures can exhibit the optimal gas-sensing behavior with the sensitivity up to 53.1 and the response and recovery times decreasing to 9 and 2.5 s at the operating temperature of 260 °C, respectively. The enhanced gas-sensing performance can be mainly attributed to the combination of uniform porous structures, narrow size-distribution, large specific surface area, and heterostructures of the interface between α-Fe2O3 and SnO2.