title: Hierarchical Assembly of α-Fe2O3Nanorods on Multiwall Carbon Nanotubes as a High-Performance Sensing Material for Gas Sensors.
abstract: This paper presents a facile hydrolysis reaction and annealing for preparing a novel hierarchical nanoheterostructure via assembly of α-Fe2O3nanorods onto multiwall carbon nanotubes (MWCNTs) backbones. The as-synthesized nanocomposites were characterized using XRD (X-ray diffraction), FESEM (Field emission scanning electron microscopy), TEM (Transmission electron microscopy), XPS (X-ray photoelectron spectroscopy) and BET (Surface Area and Porosity System). The observations showed uniform α-Fe2O3nanorods approximately 100-200 nm in length and 50-100 nm in diameter that were hierarchically assembled onto the surface of the MWCNTs. The formation of the heterostructure was investigated by observing the evolution of the microstructure of the products at different reaction times. The X-ray photoelectron spectra (XPS) showed that the ability of the absorbing oxygen was enhanced by the formation of the heterostructure composites. Moreover, as a proof-of-concept presentation, the novel CNTs@α-Fe2O3hierarchical heterostructure acted as a gas sensitive material. Significantly, the composites exhibited excellent sensing properties for acetone with high sensitivity, exceptional selectivity and good reproducibility. The response of the CNTs@α-Fe2O3sensor to 100 ppm acetones at 225 °C was nearly 35, which was superior to the single α-Fe2O3nanorods with a response of 16, and the detection limit of the sensor was 500 ppb. The enhanced properties were mainly attributed to the unique structure and p-n heterojunction between the CNTs and the α-Fe2O3nanorods.
authors.affiliation: College of Electron Science and Engineering, JiLin University , 2699 Qianjin Street, Changchun 130012, China.
authors.forename: Mingjun
authors.initials: M
authors.lastname: Dai
authors.affiliation: College of Electron Science and Engineering, JiLin University , 2699 Qianjin Street, Changchun 130012, China.
authors.forename: Liupeng
authors.initials: L
authors.lastname: Zhao
authors.affiliation: College of Electron Science and Engineering, JiLin University , 2699 Qianjin Street, Changchun 130012, China.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Gao
authors.affiliation: College of Electron Science and Engineering, JiLin University , 2699 Qianjin Street, Changchun 130012, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Sun
authors.affiliation: College of Electron Science and Engineering, JiLin University , 2699 Qianjin Street, Changchun 130012, China.
authors.forename: Fengmin
authors.initials: F
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials College of Chemistry, Jilin University , 2699 Qianjin Street, Changchun 130012, China.
authors.forename: Sean
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Department of Energy and Material Sciences, Faculty of Engineering Sciences, Kyushu University , Kasuga-shi, Fukuoka 816-8580, Japan.
authors.forename: Kengo
authors.initials: K
authors.lastname: Shimanoe
authors.affiliation: Department of Energy and Material Sciences, Faculty of Engineering Sciences, Kyushu University , Kasuga-shi, Fukuoka 816-8580, Japan.
authors.forename: Noboru
authors.initials: N
authors.lastname: Yamazoe
authors.affiliation: College of Electron Science and Engineering, JiLin University , 2699 Qianjin Street, Changchun 130012, China.
authors.forename: Geyu
authors.identifier: http://orcid.org/0000-0002-7428-2456
authors.initials: G
authors.lastname: Lu
keywords: CNTs; gas sensors; p−n heterojunction; α-Fe2O3