title: Solution-Processed Gas Sensors Employing SnO2 Quantum Dot/MWCNT Nanocomposites.
abstract: Solution-processed SnO2 colloidal quantum dots (CQDs) have emerged as an important new class of gas-sensing materials due to their potential for low-cost and high-throughput fabrication. Here we employed the design strategy based on the synergetic effect from highly sensitive SnO2 CQDs and excellent conductive properties of multiwalled carbon nanotubes (MWCNTs) to overcome the transport barrier in CQD gas sensors. The attachment and coverage of SnO2 CQDs on the MWCNT surfaces were achieved by simply mixing the presynthesized SnO2 CQDs and MWCNTs at room temperature. Compared to the pristine SnO2 CQDs, the sensor based on SnO2 quantum dot/MWCNT nanocomposites exhibited a higher response upon exposure to H2S, and the response toward 50 ppm of H2S at 70 °C was 108 with the response and recovery time being 23 and 44 s. Because of the favorable energy band alignment, the MWCNTs can serve as the acceptor of the electrons that are injected from H2S into SnO2 quantum dots in addition to the charge transport highway to direct the electron flow to the electrode, thereby enhancing the sensor response. Our research results open an easy pathway for developing highly sensitive and low-cost gas sensors.
authors.affiliation: School of Optical and Electronic Information and ‡Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology , 1037 Luoyu Road, 430074 Wuhan, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Liu
authors.affiliation: School of Optical and Electronic Information and ‡Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology , 1037 Luoyu Road, 430074 Wuhan, China.
authors.forename: Wenkai
authors.initials: W
authors.lastname: Zhang
authors.affiliation: School of Optical and Electronic Information and ‡Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology , 1037 Luoyu Road, 430074 Wuhan, China.
authors.forename: Haoxiong
authors.initials: H
authors.lastname: Yu
authors.affiliation: School of Optical and Electronic Information and ‡Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology , 1037 Luoyu Road, 430074 Wuhan, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Gao
authors.affiliation: School of Optical and Electronic Information and ‡Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology , 1037 Luoyu Road, 430074 Wuhan, China.
authors.forename: Zhilong
authors.initials: Z
authors.lastname: Song
authors.affiliation: School of Optical and Electronic Information and ‡Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology , 1037 Luoyu Road, 430074 Wuhan, China.
authors.forename: Songman
authors.initials: S
authors.lastname: Xu
authors.affiliation: School of Optical and Electronic Information and ‡Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology , 1037 Luoyu Road, 430074 Wuhan, China.
authors.forename: Min
authors.initials: M
authors.lastname: Li
authors.affiliation: School of Optical and Electronic Information and ‡Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology , 1037 Luoyu Road, 430074 Wuhan, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Optical and Electronic Information and ‡Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology , 1037 Luoyu Road, 430074 Wuhan, China.
authors.forename: Haisheng
authors.initials: H
authors.lastname: Song
authors.affiliation: School of Optical and Electronic Information and ‡Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology , 1037 Luoyu Road, 430074 Wuhan, China.
authors.forename: Jiang
authors.initials: J
authors.lastname: Tang
keywords: MWCNT; colloidal quantum dot; gas sensor; hydrogen sulfide; tin oxide