Construction of mesoporous In2O3-ZnO hierarchical structure gas sensor for ethanol detection

The development of mesoporous heterogeneous structure through a facile and repeatable method with high gas sensing performance is always highly desirable in the chemical sensor field. Herein, the mesoporous In2O3-ZnO heterogeneous structure has been successfully synthesized via a reproducible hydrothermal method. The characterizations of sensing materials demonstrate that the porous heterogeneous structure can be easily constructed. Gas sensing investigation indicates that the gas sensor based on 15 at. % In2O3-ZnO exhibits the obvious enhanced ethanol gas sensing performances compared with that based on pure ZnO material in our previous work, including lower detection limit (200 ppb), lower base line resistance (∼ 1 Mohm), satisfying long term stability and improved moisture tolerance. The enhanced gas sensing properties can be mainly attributed to the In2O3-ZnO heterogeneous structure and unique microstructure, which will be deliberately discussed in the sensing mechanism part.