Chemiresistive gas sensors employing solution-processed metal oxide quantum dot films

Journal Article · Mon Oct 20 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4900405· OSTI ID:22350977

Liu, Huan; Xu, Songman; Li, Min; Shao, Gang; Zhang, Wenkai; Wei, Wendian; He, Mingze ^[1]; Song, Huaibing; Gao, Liang; Song, Haisheng; Tang, Jiang ^[2]

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1. School of Optical and Electronic Information, Huazhong University of Science and Technology, 1037 Luoyu Rd., Wuhan, Hubei 430074 (China)
2. Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, 1037 Luoyu Rd., Wuhan, Hubei 430074 (China)

We report low-temperature chemiresistive gas sensors based on tin oxide colloidal quantum dots (CQDs), in which the benefits of CQDs such as extremely small crystal size, solution-processability, and tunable surface activity are exploited to enhance the gas-sensing effect. The sensor fabrication is simply employing spin-coating followed by a solid-state ligand exchange treatment at room temperature in air ambient. The optimal gas sensor exhibited rapid and significant decrease in resistance upon H{sub 2}S gas exposure when operated at 70 °C, and it was fully recoverable upon gas release. We observed a power law correlation between the sensor response and H{sub 2}S gas concentration, and the sensing mechanism was discussed using the completely depletion model with a flat band diagram.

• OSTI ID: 22350977
• Journal Information: Applied Physics Letters, Vol. 105, Issue 16; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COLLOIDS
CORRELATIONS
CRYSTALS
ELECTRIC CONDUCTIVITY
ELECTRONIC STRUCTURE
FILMS
GASES
HYDROGEN SULFIDES
ION EXCHANGE
METALS
QUANTUM DOTS
SENSORS
SOLIDS
SPIN-ON COATING
SURFACE PROPERTIES
SURFACES
TEMPERATURE RANGE 0273-0400 K
TIN OXIDES