Effect of Ni, Pd, and Pt Nanoparticle Dispersion on Thick Films of TiO2 Nanotubes for Hydrogen Sensing: TEM and XPS Studies
| Autor: | K. I. Gnanasekar, T. Manovah David, P. Wilson, Tom Mathews, P. Sagayaraj |
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| Rok vydání: | 2020 |
| Předmět: |
Materials science
Hydrogen General Chemical Engineering Physics::Optics chemistry.chemical_element Nanoparticle General Chemistry Crystal structure Nanoparticle dispersion Article Chemistry Condensed Matter::Materials Science Nickel X-ray photoelectron spectroscopy chemistry Chemical engineering Group (periodic table) Condensed Matter::Superconductivity QD1-999 |
| Zdroj: | ACS Omega, Vol 5, Iss 20, Pp 11352-11360 (2020) ACS Omega |
| ISSN: | 2470-1343 |
| DOI: | 10.1021/acsomega.0c00292 |
| Popis: | Crystal structure, morphological features, and hydrogen-sensing properties of thick film sensors of TiO2 nanotubes (NTs) impregnated with nanoparticles of elements of Group 10, viz., nickel, palladium, and platinum, having average grain size of about 25, 20, and 20 nm, respectively, are presented. The sensitivity is observed to be higher for Pd/TiO2 NTs than for Pt/TiO2 NTs. Ni/TiO2 NTs exhibited very poor sensitivity. X-ray photoelectron spectroscopy (XPS) studies confirm reduction of the oxide layer of palladium nanoparticles, which, in turn, is responsible for the generation of Ti3+ ion in TiO2 NTs through hydrogen spillover. For Pt/TiO2 NTs, only reduction of the oxide layer over Pt nanoparticles takes place without any spillover effect. For Ni/TiO2 NTs, neither NiO nor TiO2 undergoes any reduction. Changes in the Fermi level difference of PdO and TiO2 along with Ti3+ generation synergistically operate for Pd/TiO2 NTs, whereas the difference in Fermi levels of PtO and TiO2 alone operates for Pt/TiO2 NTs during sensing. |
| Databáze: | OpenAIRE |
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