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A Room Temperature H₂ Sensor Fabricated Using High Performance Pt-Loaded SnO₂ Nanoparticles.

Wang SC, Shaikh MO - Sensors (Basel) (2015)

Bottom Line: Using Pt as catalyst improved sensor response and reduced the operating temperature for achieving high sensitivity because of the negative temperature coefficient observed in Pt-loaded SnO2.The highest sensor response to 1000 ppm H2 was 10,500 at room temperature with a response time of 20 s.The morphology of the SnO2 nanoparticles, the surface loading concentration and dispersion of the Pt catalyst and the microstructure of the sensing layer all play a key role in the development of an effective gas sensing device.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical Engineering, Southern Taiwan University of Science and Technology, Tainan 710, Taiwan. scwang@mail.stust.edu.tw.

ABSTRACT
Highly sensitive H2 gas sensors were prepared using pure and Pt-loaded SnO2 nanoparticles. Thick film sensors (~35 μm) were fabricated that showed a highly porous interconnected structure made of high density small grained nanoparticles. Using Pt as catalyst improved sensor response and reduced the operating temperature for achieving high sensitivity because of the negative temperature coefficient observed in Pt-loaded SnO2. The highest sensor response to 1000 ppm H2 was 10,500 at room temperature with a response time of 20 s. The morphology of the SnO2 nanoparticles, the surface loading concentration and dispersion of the Pt catalyst and the microstructure of the sensing layer all play a key role in the development of an effective gas sensing device.

No MeSH data available.


Related in: MedlinePlus

(a) Gas sensitivity as a function of operating temperature for pure SnO2 thick film sensor. Change in resistance of pure SnO2 gas sensors on exposure to 1000 ppm of H2 for 10 cycles at an operating temperature of (b) 200 °C, (c) 300 °C and (d) 400 °C.
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sensors-15-14286-f002: (a) Gas sensitivity as a function of operating temperature for pure SnO2 thick film sensor. Change in resistance of pure SnO2 gas sensors on exposure to 1000 ppm of H2 for 10 cycles at an operating temperature of (b) 200 °C, (c) 300 °C and (d) 400 °C.

Mentions: In our previous report [26] we studied the transformation of the tin oleate precursor under nitrogen (N2) atmosphere and found that the SnO changes morphology from tetrahedral (30 min) to decahedral (3 h) but does not transform structurally into SnO2. On the basis of the experimental results, we can propose a mechanism for the formation of SnO2 nanoparticles. As the TOA was added into the tin oleate complex solution and heated to 340 °C, the tin oleate decomposed into SnO monomers. The coordinating solvent TOA works as an activator to trigger the decomposition reaction as well as a surfactant to control the shape of the SnO particles. The SnO monomers are like building blocks which assemble into larger SnO nanosheets to minimize the surface energy. When TOA is absorbed isotropically on the surface in the presence of N2, it is unstable in air and selectively absorbs on the (001) plane and thus the two reaction conditions result in different morphologies of SnO. Heating in air for 3 h causes the SnO nanosheets to transform into the more energetically stable SnO2 phase. The synthesized pure SnO2 nanoparticles were made into a thick film sensor (Sensor A) as described in the experimental section and the sensitivity and response time measurements at different operating temperatures can be shown in Figure 2.


A Room Temperature H₂ Sensor Fabricated Using High Performance Pt-Loaded SnO₂ Nanoparticles.

Wang SC, Shaikh MO - Sensors (Basel) (2015)

(a) Gas sensitivity as a function of operating temperature for pure SnO2 thick film sensor. Change in resistance of pure SnO2 gas sensors on exposure to 1000 ppm of H2 for 10 cycles at an operating temperature of (b) 200 °C, (c) 300 °C and (d) 400 °C.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4507593&req=5

sensors-15-14286-f002: (a) Gas sensitivity as a function of operating temperature for pure SnO2 thick film sensor. Change in resistance of pure SnO2 gas sensors on exposure to 1000 ppm of H2 for 10 cycles at an operating temperature of (b) 200 °C, (c) 300 °C and (d) 400 °C.
Mentions: In our previous report [26] we studied the transformation of the tin oleate precursor under nitrogen (N2) atmosphere and found that the SnO changes morphology from tetrahedral (30 min) to decahedral (3 h) but does not transform structurally into SnO2. On the basis of the experimental results, we can propose a mechanism for the formation of SnO2 nanoparticles. As the TOA was added into the tin oleate complex solution and heated to 340 °C, the tin oleate decomposed into SnO monomers. The coordinating solvent TOA works as an activator to trigger the decomposition reaction as well as a surfactant to control the shape of the SnO particles. The SnO monomers are like building blocks which assemble into larger SnO nanosheets to minimize the surface energy. When TOA is absorbed isotropically on the surface in the presence of N2, it is unstable in air and selectively absorbs on the (001) plane and thus the two reaction conditions result in different morphologies of SnO. Heating in air for 3 h causes the SnO nanosheets to transform into the more energetically stable SnO2 phase. The synthesized pure SnO2 nanoparticles were made into a thick film sensor (Sensor A) as described in the experimental section and the sensitivity and response time measurements at different operating temperatures can be shown in Figure 2.

Bottom Line: Using Pt as catalyst improved sensor response and reduced the operating temperature for achieving high sensitivity because of the negative temperature coefficient observed in Pt-loaded SnO2.The highest sensor response to 1000 ppm H2 was 10,500 at room temperature with a response time of 20 s.The morphology of the SnO2 nanoparticles, the surface loading concentration and dispersion of the Pt catalyst and the microstructure of the sensing layer all play a key role in the development of an effective gas sensing device.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical Engineering, Southern Taiwan University of Science and Technology, Tainan 710, Taiwan. scwang@mail.stust.edu.tw.

ABSTRACT
Highly sensitive H2 gas sensors were prepared using pure and Pt-loaded SnO2 nanoparticles. Thick film sensors (~35 μm) were fabricated that showed a highly porous interconnected structure made of high density small grained nanoparticles. Using Pt as catalyst improved sensor response and reduced the operating temperature for achieving high sensitivity because of the negative temperature coefficient observed in Pt-loaded SnO2. The highest sensor response to 1000 ppm H2 was 10,500 at room temperature with a response time of 20 s. The morphology of the SnO2 nanoparticles, the surface loading concentration and dispersion of the Pt catalyst and the microstructure of the sensing layer all play a key role in the development of an effective gas sensing device.

No MeSH data available.


Related in: MedlinePlus