title: Room temperature NO2 sensing: what advantage does the rGO-NiO nanocomposite have over pristine NiO?
abstract: In recent years, there has been increasing interest in synthesis of reduced graphene oxide (rGO)-metal oxide semiconductor (MOS) nanocomposites for room temperature gas sensing applications. Generally, the sensitivity of a MOS can be obviously enhanced by the incorporation of rGO. However, a lack of knowledge regarding how rGO can enhance gas-sensing performances of MOSs impedes its sensing applications. Herein, in order to get an insight into the sensing mechanism of rGO-MOS nanocomposites and further improve the sensing performances of NiO-based sensors at room temperature, an rGO-NiO nanocomposite was synthesized. Through a comparison study on room temperature NO2 sensing of rGO-NiO and pristine NiO, an inverse gas-sensing behavior in different NO2 concentration ranges was observed and the sensitivity of rGO-NiO was enhanced obviously in the high concentration range (7-60 ppm). Significantly, the stimulating effect of rGO on the recovery rate was confirmed by the sensing characteristics of rGO-NiO that was advantageous for the development of NO2 sensors at room temperature. By comprehending the electronic interactions between the rGO-MOS nanocomposite and the target gas, this work may open up new possibilities for further improvement of graphene-based hybrid materials with even higher sensing performances.
authors.affiliation: State Key Laboratory of Materials Processing and Die Mould Technology, Huazhong University of Science and Technology (HUST), No. 1037, Luoyu Road, Wuhan 430074, China. dwzeng@mail.hust.edu.cn.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.forename: Dawen
authors.initials: D
authors.lastname: Zeng
authors.forename: Shiqian
authors.initials: S
authors.lastname: Zhao
authors.forename: Jinjin
authors.initials: J
authors.lastname: Wu
authors.forename: Keng
authors.initials: K
authors.lastname: Xu
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhu
authors.forename: Guozhu
authors.initials: G
authors.lastname: Zhang
authors.forename: Changsheng
authors.initials: C
authors.lastname: Xie