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Detecting hydrogen using graphene quantum dots/WO3 thin films
| Content Provider | Scilit |
|---|---|
| Author | Fardindoost, Somayeh Zad, Azam Iraji Hosseini, Zahra Sadat Hatamie, Shadie |
| Copyright Year | 2016 |
| Description | Journal: Materials Research Express In the present work we report an approach to resistive hydrogen sensing based on graphene quantum dots $(GQDs)/WO_{3}$ thin films that work reproducibly at low temperatures. GQDs were chemically synthesized and evenly dispersed in $WO_{3}$ solution with 1:1 molar ratio. The structural evaluation and crystallization of the prepared films was studied by x-ray diffraction, Raman and scanning electron microscopy (SEM) techniques. The SEM images showed uniform distribution of the GQDs in $WO_{3}$ films with sizes around 50 nm. Raman experiment showed the GQDs are partially reduced with high edge defects as hydroxyl and carboxyl groups which involve both in bridging between $WO_{3}$ grains via bindings as well as interacting with target gas molecules. GQDs can develop an electron conductive network and shorten the current transport paths inside the sensitive films. As a result, they improved the poor electrical properties and charge transfer of pure $WO_{3}$. Resistive hydrogen sensing showed significant decrease in the working temperature for $GQDs/WO_{3}$ films compared to pure $WO_{3}$ films. The working temperature of about 150 °C with 15 and 40 s response and recovery times are significant characteristics of the introduced sensing structure. Then palladium (Pd) was added as a catalyst in $GQDs/WO_{3}$ film to make the sensing materials selective to hydrogen. Pd doped film worked at temperature of 120 °C with high selectivity and improved response magnitude to hydrogen gas. |
| Related Links | http://iopscience.iop.org/article/10.1088/2053-1591/3/11/116407/pdf |
| ISSN | 20531591 |
| e-ISSN | 20531591 |
| DOI | 10.1088/2053-1591/3/11/116407 |
| Journal | Materials Research Express |
| Issue Number | 11 |
| Volume Number | 3 |
| Language | English |
| Publisher | IOP Publishing |
| Publisher Date | 2016-11-01 |
| Access Restriction | Open |
| Subject Keyword | Journal: Materials Research Express Resistive Hydrogen Sensing |
| Content Type | Text |
| Resource Type | Article |
| Subject | Surfaces, Coatings and Films Metals and Alloys Biomaterials Electronic, Optical and Magnetic Materials Polymers and Plastics |
