title: Nanowire-Assembled Hierarchical ZnCo2O4Microstructure Integrated with a Low-Power Microheater for Highly Sensitive Formaldehyde Detection.
abstract: Nanowire-assembled 3D hierarchical ZnCo2O4microstructure is synthesized by a facile hydrothermal route and a subsequent annealing process. In comparison to simple nanowires, the resulting dandelion-like structure yields more open spaces between nanowires, which allow for better gas diffusion and provide more active sites for gas adsorption while maintaining good electrical conductivity. The hierarchical ZnCo2O4microstructure is integrated on a low-power microheater platform without using binders or conductive additives. The hierarchical structure of the ZnCo2O4sensing material provides reliable electrical connection across the sensing electrodes. The resulting sensor exhibits an ultralow detection limit of 3 ppb toward formaldehyde with fast response and recovery as well as good selectivity to CO, H2, and hydrocarbons such as n-pentane, propane, and CH4. The sensor only consumes ∼5.7 mW for continuous operation at 300 °C with good long-term stability. The excellent sensing performance of this hierarchical structure based sensor suggests the advantages of combining such structures with microfabricated heaters for practical low-power sensing applications.
authors: State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology , Wuhan 430074, China.
authors: Hu
authors: H
authors: Long
authors: Anna
authors: A
authors: Harley-Trochimczyk
authors: State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology , Wuhan 430074, China.
authors: Siyi
authors: S
authors: Cheng
authors: State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology , Wuhan 430074, China.
authors: Hao
authors: H
authors: Hu
authors: Won Seok
authors: WS
authors: Chi
authors: Ameya
authors: A
authors: Rao
authors: Carlo
authors: C
authors: Carraro
authors: State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology , Wuhan 430074, China.
authors: Tielin
authors: T
authors: Shi
authors: State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology , Wuhan 430074, China.
authors: Zirong
authors: Z
authors: Tang
authors: Roya
authors: R
authors: Maboudian
keywords: ZnCo2O4; formaldehyde; hierarchical structure; microheater; sensing