Hydrogen-Sensing Properties of Ultrathin Pt-Co Alloy Films
The present work aims to investigate the feasibility of utilizing Pt and PtCo alloy ultrathin films as hydrogen gas sensors in order to reduce the cost of the hydrogen gas sensors by using low-cost metallic materials. In this study, ultrathin Pt and PtCo alloy thin films are evaluated for hydrogen s...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-12-01
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| Series: | Chemosensors |
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| Online Access: | https://www.mdpi.com/2227-9040/10/12/512 |
| _version_ | 1797460882001756160 |
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| author | Mustafa Erkovan Caner Deger Susana Cardoso Necmettin Kilinc |
| author_facet | Mustafa Erkovan Caner Deger Susana Cardoso Necmettin Kilinc |
| author_sort | Mustafa Erkovan |
| collection | DOAJ |
| description | The present work aims to investigate the feasibility of utilizing Pt and PtCo alloy ultrathin films as hydrogen gas sensors in order to reduce the cost of the hydrogen gas sensors by using low-cost metallic materials. In this study, ultrathin Pt and PtCo alloy thin films are evaluated for hydrogen sensors. The stoichiometry and structural characterization of the thin films are observed from XPS, SEM, and EDX measurements. The 2-nm-thick Pt and PtCo films deposited by sputtering onto Si/SiO<sub>2</sub> covers homogeneously the surface in an fcc crystalline plane (111). The hydrogen gas-sensing properties of the films are assessed from the resistance measurement between 25 °C and 150 °C temperature range, under atmospheres with hydrogen concentration ranging from 10 ppm to 5%. The hydrogen-sensing mechanism of ultrathin Pt<sub>x</sub>Co<sub>1-x</sub> alloy films can be elucidated with the surface scattering phenomenon. PtCo thin alloy films show better response time than pure Pt thin films, but the alloy films show lower sensor response than pure Pt film’s sensor response. Aside from these experimental investigations, first-principles calculations have also been carried out for bare Pt and Co, and also PtCo alloys. Compared to the theoretical calculations, the sensor response to change decreases with increasing Co content, a result that is compatible with the experimental results. In an attempt to explain the decrease in the sensor response of PtCo alloy films compared to bare Pt film, a variety of different phenomena are discussed, including the shrinking lattice of the structure or dendritic surface structure of PtCo alloy films by the increasing cobalt ratio. |
| first_indexed | 2024-03-09T17:12:25Z |
| format | Article |
| id | doaj.art-738310b210c44a5992ef34e25e89e88a |
| institution | Directory Open Access Journal |
| issn | 2227-9040 |
| language | English |
| last_indexed | 2024-03-09T17:12:25Z |
| publishDate | 2022-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Chemosensors |
| spelling | doaj.art-738310b210c44a5992ef34e25e89e88a2023-11-24T13:59:14ZengMDPI AGChemosensors2227-90402022-12-01101251210.3390/chemosensors10120512Hydrogen-Sensing Properties of Ultrathin Pt-Co Alloy FilmsMustafa Erkovan0Caner Deger1Susana Cardoso2Necmettin Kilinc3Instituto de Engenharia de Sistemas E Computadores—Microsistemas e Nanotecnologias (INESC MN), 1000-029 Lisbon, PortugalDepartment of Physics, Marmara University, Ziverbey, 34722 Istanbul, TürkiyeInstituto de Engenharia de Sistemas E Computadores—Microsistemas e Nanotecnologias (INESC MN), 1000-029 Lisbon, PortugalDepartment of Physics, Inonu University, 44280 Malatya, TürkiyeThe present work aims to investigate the feasibility of utilizing Pt and PtCo alloy ultrathin films as hydrogen gas sensors in order to reduce the cost of the hydrogen gas sensors by using low-cost metallic materials. In this study, ultrathin Pt and PtCo alloy thin films are evaluated for hydrogen sensors. The stoichiometry and structural characterization of the thin films are observed from XPS, SEM, and EDX measurements. The 2-nm-thick Pt and PtCo films deposited by sputtering onto Si/SiO<sub>2</sub> covers homogeneously the surface in an fcc crystalline plane (111). The hydrogen gas-sensing properties of the films are assessed from the resistance measurement between 25 °C and 150 °C temperature range, under atmospheres with hydrogen concentration ranging from 10 ppm to 5%. The hydrogen-sensing mechanism of ultrathin Pt<sub>x</sub>Co<sub>1-x</sub> alloy films can be elucidated with the surface scattering phenomenon. PtCo thin alloy films show better response time than pure Pt thin films, but the alloy films show lower sensor response than pure Pt film’s sensor response. Aside from these experimental investigations, first-principles calculations have also been carried out for bare Pt and Co, and also PtCo alloys. Compared to the theoretical calculations, the sensor response to change decreases with increasing Co content, a result that is compatible with the experimental results. In an attempt to explain the decrease in the sensor response of PtCo alloy films compared to bare Pt film, a variety of different phenomena are discussed, including the shrinking lattice of the structure or dendritic surface structure of PtCo alloy films by the increasing cobalt ratio.https://www.mdpi.com/2227-9040/10/12/512gas sensorplatinumplatinum-cobalt alloysthin filmshydrogen sensor |
| spellingShingle | Mustafa Erkovan Caner Deger Susana Cardoso Necmettin Kilinc Hydrogen-Sensing Properties of Ultrathin Pt-Co Alloy Films Chemosensors gas sensor platinum platinum-cobalt alloys thin films hydrogen sensor |
| title | Hydrogen-Sensing Properties of Ultrathin Pt-Co Alloy Films |
| title_full | Hydrogen-Sensing Properties of Ultrathin Pt-Co Alloy Films |
| title_fullStr | Hydrogen-Sensing Properties of Ultrathin Pt-Co Alloy Films |
| title_full_unstemmed | Hydrogen-Sensing Properties of Ultrathin Pt-Co Alloy Films |
| title_short | Hydrogen-Sensing Properties of Ultrathin Pt-Co Alloy Films |
| title_sort | hydrogen sensing properties of ultrathin pt co alloy films |
| topic | gas sensor platinum platinum-cobalt alloys thin films hydrogen sensor |
| url | https://www.mdpi.com/2227-9040/10/12/512 |
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