Hydrogen Sensing Performance of ZnO Schottky Diodes in Humid Ambient Conditions with PMMA Membrane Layer
Enhanced hydrogen sensing performance of Pt Schottky diodes on ZnO single crystal wafers in humid ambient conditions is reported using a polymethylmethacrylate (PMMA) membrane layer. ZnO diode sensors showed little change in forward current when switching to wet ambient H<sub>2</sub> con...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-02-01
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| Series: | Sensors |
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| Online Access: | https://www.mdpi.com/1424-8220/20/3/835 |
| _version_ | 1798038105464242176 |
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| author | Soohwan Jang Sunwoo Jung Kwang Hyeon Baik |
| author_facet | Soohwan Jang Sunwoo Jung Kwang Hyeon Baik |
| author_sort | Soohwan Jang |
| collection | DOAJ |
| description | Enhanced hydrogen sensing performance of Pt Schottky diodes on ZnO single crystal wafers in humid ambient conditions is reported using a polymethylmethacrylate (PMMA) membrane layer. ZnO diode sensors showed little change in forward current when switching to wet ambient H<sub>2</sub> conditions with 100% relative humidity. This sensitivity drop in the presence of water vapor can be attributed to surface coverage of hydroxyl groups on the Pt surface in humid ambient conditions. The hydrogen sensitivity of PMMA-coated diode sensors recovered up to 805% in wet H<sub>2</sub> ambient conditions at room temperature. The PMMA layer can selectively filter water vapor and allow H<sub>2</sub> molecules to pass through the membrane layer. It is clear that the PMMA layer can effectively serve as a moisture barrier because of low water vapor permeability and its hydrophobicity. In both dry and wet conditions, ZnO diodes exhibited relatively fast and stable on/off switching in each cycle with good repeatability. |
| first_indexed | 2024-04-11T21:35:41Z |
| format | Article |
| id | doaj.art-45aa48383b8c4635bbfeb59203e21f26 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-04-11T21:35:41Z |
| publishDate | 2020-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-45aa48383b8c4635bbfeb59203e21f262022-12-22T04:01:46ZengMDPI AGSensors1424-82202020-02-0120383510.3390/s20030835s20030835Hydrogen Sensing Performance of ZnO Schottky Diodes in Humid Ambient Conditions with PMMA Membrane LayerSoohwan Jang0Sunwoo Jung1Kwang Hyeon Baik2Department of Chemical Engineering, Dankook University, Yongin 16890, KoreaDepartment of Chemical Engineering, Dankook University, Yongin 16890, KoreaDepartment of Materials Science and Engineering, Hongik University, Sejong 30016, KoreaEnhanced hydrogen sensing performance of Pt Schottky diodes on ZnO single crystal wafers in humid ambient conditions is reported using a polymethylmethacrylate (PMMA) membrane layer. ZnO diode sensors showed little change in forward current when switching to wet ambient H<sub>2</sub> conditions with 100% relative humidity. This sensitivity drop in the presence of water vapor can be attributed to surface coverage of hydroxyl groups on the Pt surface in humid ambient conditions. The hydrogen sensitivity of PMMA-coated diode sensors recovered up to 805% in wet H<sub>2</sub> ambient conditions at room temperature. The PMMA layer can selectively filter water vapor and allow H<sub>2</sub> molecules to pass through the membrane layer. It is clear that the PMMA layer can effectively serve as a moisture barrier because of low water vapor permeability and its hydrophobicity. In both dry and wet conditions, ZnO diodes exhibited relatively fast and stable on/off switching in each cycle with good repeatability.https://www.mdpi.com/1424-8220/20/3/835gas sensorznohumidityhydrogenschottky diode |
| spellingShingle | Soohwan Jang Sunwoo Jung Kwang Hyeon Baik Hydrogen Sensing Performance of ZnO Schottky Diodes in Humid Ambient Conditions with PMMA Membrane Layer Sensors gas sensor zno humidity hydrogen schottky diode |
| title | Hydrogen Sensing Performance of ZnO Schottky Diodes in Humid Ambient Conditions with PMMA Membrane Layer |
| title_full | Hydrogen Sensing Performance of ZnO Schottky Diodes in Humid Ambient Conditions with PMMA Membrane Layer |
| title_fullStr | Hydrogen Sensing Performance of ZnO Schottky Diodes in Humid Ambient Conditions with PMMA Membrane Layer |
| title_full_unstemmed | Hydrogen Sensing Performance of ZnO Schottky Diodes in Humid Ambient Conditions with PMMA Membrane Layer |
| title_short | Hydrogen Sensing Performance of ZnO Schottky Diodes in Humid Ambient Conditions with PMMA Membrane Layer |
| title_sort | hydrogen sensing performance of zno schottky diodes in humid ambient conditions with pmma membrane layer |
| topic | gas sensor zno humidity hydrogen schottky diode |
| url | https://www.mdpi.com/1424-8220/20/3/835 |
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