A bimetallic MOF-derived α-Fe2O3/In2O3 heterojunction for a cyclohexane gas sensor

Abstract

Recently, metal–organic framework (MOF)-derived semiconductors have been tremendously stimulated for application in gas sensors due to their advantages in terms of unique structures and tailored composition. In this work, a bimetal–organic framework of InFc MOF synthesized via a hydrothermal strategy is rendered as a template to convert α-Fe₂O₃/In₂O₃ heterojunctions by annealing treatment. When investigated as a gas sensing material, the optimal α-Fe₂O₃/In₂O₃ composite (calcined at 600 °C, In–Fe-6) achieves a high sensitivity (86) to 100 ppm cyclohexane at a working temperature of 225 °C, in the top set for similar types of sensors. Besides, α-Fe₂O₃/In₂O₃ exhibits high selectivity, rapid response (15 s) and excellent repeatability in sensing cyclohexane. The enhanced performance for cyclohexane sensing is also discussed in detail.