The Influence of Nb on the Synthesis of WO3 Nanowires and the Effects on Hydrogen Sensing Performance
Abstract
:1. Introduction
2. Materials and Methods
2.1. Synthesis of the Nanostructures
2.2. Morphological and Structural Characterization
2.3. Chemical Sensing Measurements
3. Morphologic and Structural Investigations
4. Functional Characterizations as Chemical Sensor
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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No Flow | 10 sccm O2 | 10 sccm Ar | |
---|---|---|---|
SEM |
WO3 | WO3 + Nb(4) | WO3 + Nb(12) | |
---|---|---|---|
500 °C | |||
550 °C | |||
600 °C | |||
650 °C | |||
700 °C |
Material | Morphology | H2 Gas Concentration | Temperature | Humidity | Response | Ref. |
---|---|---|---|---|---|---|
Pd-WO3 | Ribbon-like | 500 ppm | 100 °C | Dry air | ∆G/G = 80 | [36] |
Pd-WO3/PRGO | Irregular | 500 ppm | 100 °C | Dry air | ∆G/G = 150 | [36] |
WO3 | Thin film | 0.50% | 180 °C | Dry air | ∆G/G = 6 | [35] |
Pt-WO3 | Thin film | 0.50% | 70 °C | Dry air | ∆G/G = 450 | [35] |
Au-WO3 | Thin film | 0.50% | 262 °C | Dry air | ∆G/G = 250 | [35] |
WO3 | Nanorods | 500 ppm | 200 °C | Dry air | Rair/Rgas ≈ 1 | [37] |
Pt-WO3 | Nanorods | 500 ppm | 200 °C | Dry air | Rair/Rgas = 3 × 104 | [37] |
Pd-WO3 | Cluster film | 2% | 80 °C | Dry air | ∆G/G = 2.4 × 104 | [75] |
Pd-WO3 | Nanoparticles | 200 ppm | 200 °C | RH = 50% | ∆G/G = 20 | [38] |
Pd-WO3 | Nanoneedles | 500 ppm | 150 °C | RH = 50% | ∆G/G = 1670 | [31] |
WO3 | Nanowires | 500 ppm | 200 °C | RH = 50% | ∆G/G = 6 × 103 | This work |
WO3 + Nb(4) | Nanowires | 500 ppm | 200 °C | RH = 50% | ∆G/G = 8 × 104 | This work |
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Zappa, D. The Influence of Nb on the Synthesis of WO3 Nanowires and the Effects on Hydrogen Sensing Performance. Sensors 2019, 19, 2332. https://doi.org/10.3390/s19102332
Zappa D. The Influence of Nb on the Synthesis of WO3 Nanowires and the Effects on Hydrogen Sensing Performance. Sensors. 2019; 19(10):2332. https://doi.org/10.3390/s19102332
Chicago/Turabian StyleZappa, Dario. 2019. "The Influence of Nb on the Synthesis of WO3 Nanowires and the Effects on Hydrogen Sensing Performance" Sensors 19, no. 10: 2332. https://doi.org/10.3390/s19102332