Perovskite-structured LaFeO₃ modified In₂O₃ gas sensor with high selectivity and ultra-low detection limit for 2-butanone

LaFeO3 material with excellent performance and unique perovskite structure has attracted more and more attention in the field of VOC gas detection. However, simultaneously achieving low detection limits and high sensitivity at low temperatures is still a very valuable topic. In this study, LaFeO3-In2O3 material was prepared by hydrothermal method and used to detect 2-butanone gas. Various characterization results displayed that the LaFeO3-In2O3 material was successfully obtained. Compared with the pure In2O3 material, the LaFeO3-In2O3 material had more outstanding gas-sensing properties for 2-butanone. The response value (425) of 1% LaFeO3- In2O3 gas sensor to 100 ppm 2-butanone at 210 celcius was nearly three times that of pure In2O3. Moreover, the 1% LaFeO3-In2O3 sensor had a very low detection limit (10 ppb), excellent selectivity, repeatability, and long-term stability. The greatly enhanced sensing performance for 2-butanone can be attributed to the heterojunction-induced changes in surface properties and electronic structure, the catalytic effect of LaFeO3, and there is a synergistic effect between these two components. This study provides a very simple synthesis method, which can greatly improve the gas sensing properties of 2-butanone, which is very promising and valuable for industrial production and life.