Effects of Palladium Loading on the Response of Thick Film Flame-made ZnO Gas Sensor for Detection of Ethanol Vapor
Abstract
:1. Introduction
2. Experimental
2.1. Flame-synthesis of Pd-ZnO Nanoparticles
2.2. Particle and Doping Characterizations
2.3. Sensor Preparation
2.4. Characterization of Gas Sensing Properties and Mass Spectrometry Measurements
3. Results and Discussion
3.1. Particle Properties
3.1.1. X-ray Diffraction and BET Analyses
3.1.2. Atomic Force Microscopy (AFM) Analysis
3.1.3. Scanning Electron Microscopy (SEM) Analysis
3.1.4. High Resolution-Transmission Electron Microscopy (HR-TEM) Analysis
3.1.5. Scanning-Transmission Electron Microscopy (STEM) Analysis
3.1.6. CO-pulse Chemisorption Measurement
3.2. Gas Sensing Properties
- -
- Nanostructuring of the based-semiconducting oxide also contributes to the improvement in the gas response by larger surface area because here the complete particle contributes to the gas sensing phenomenon (D ~ 2L, where D is the particle diameter and L is the Debye length). The larger surface area of the materials synthesized also facilitates the gas detection at much lower temperatures [43]. In addition, palladium is known to have a catalytic effect due to its excellent oxidation capability to convert hydrocarbons at lower temperatures making the sensor selective to hydrocarbons [43-45].
3.3. SEM-Film thickness sensing layer
4. Conclusions
Acknowledgments
References
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Liewhiran, C.; Phanichphant, S. Effects of Palladium Loading on the Response of Thick Film Flame-made ZnO Gas Sensor for Detection of Ethanol Vapor. Sensors 2007, 7, 1159-1184. https://doi.org/10.3390/s7071159
Liewhiran C, Phanichphant S. Effects of Palladium Loading on the Response of Thick Film Flame-made ZnO Gas Sensor for Detection of Ethanol Vapor. Sensors. 2007; 7(7):1159-1184. https://doi.org/10.3390/s7071159
Chicago/Turabian StyleLiewhiran, Chaikarn, and Sukon Phanichphant. 2007. "Effects of Palladium Loading on the Response of Thick Film Flame-made ZnO Gas Sensor for Detection of Ethanol Vapor" Sensors 7, no. 7: 1159-1184. https://doi.org/10.3390/s7071159