Diffusion-controlled H2 sensors composed of Pd-coated highly porous WO3 nanocluster films
| Autor: | Chung Wo Ong, Jian Xing Huang, Meng Zhao |
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| Rok vydání: | 2014 |
| Předmět: |
Resistive touchscreen
Materials science Metals and Alloys Response time Nanotechnology Condensed Matter Physics Hydrogen sensor Dissociation (chemistry) Surfaces Coatings and Films Electronic Optical and Magnetic Materials Catalysis Chemical engineering Electrode Materials Chemistry Molecule Electrical and Electronic Engineering Porosity Instrumentation |
| Zdroj: | Sensors and Actuators B: Chemical. 191:711-718 |
| ISSN: | 0925-4005 |
| Popis: | The resistive H 2 sensing properties of palladium-coated highly porous tungsten oxide nanocluster films (Pd/WO 3 ), with the WO 3 layers having different thicknesses (11.2–153 nm) and electrodes at different positions, were investigated at 80 °C. The results were interpreted by using a model involving various mechanisms including surface catalytic dissociation of the H 2 and O 2 molecules, spillover and diffusion of the split species on the surface and inside the WO 3 layer respectively, and the interaction between the species. The validity of the model was further examined by investigating the influences of the WO 3 thickness and the electrode position on the H 2 sensing properties. The results of data analysis confirm the important role of the diffusion of the split species in the WO 3 layer. The optimum sensor is characterized by having an ultrathin WO 3 nanocluster film with a thickness ≈11 nm, which exhibits a strong sensor response; short response time and recovery time, and stable resistant output during the hydrogenation process. |
| Databáze: | OpenAIRE |
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