| Author | Sivapunniyam, Aarthy |
| Call Number | AIT Thesis no.ME-10-02 |
| Subject(s) | Nanostructures
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Microelectronics, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. ME-10-02 |
| Abstract | Gas sensors are used in areas such as personal safety, environmental monitoring, household and industrial applications. Each application requires different levels of sensor performance. During the course of this thesis research, we fabricated ZnO nanostructures based gas sensors using simple and efficient hydrothermal method. The major focus was oriented towards enhancing the sensor performance for detection of harmful gases like LPG and ammonia. Ethanol sensors with very high sensitivity and stability are urgently needed in the field of chemical and food industries, breath analyzer and quality monitoring. Change in conductivity when exposed to harmful gases is sensed. Noble metal catalysts like platinum in nanodimensions were also used to enhance the sensor performance. In a previous research work reported from our laboratory, ZnO nanorods based gas sensors were fabricated on glass substrates using hydrothermal method. Maximum sensitivity of 58% was achieved for 9000 ppm LPG and 25% for ethanol at 6000 ppm at 250ºC. The goal was to improve the sensitivity of gas sensor using nanostructures of zinc oxide and zinc stannate. Therefore in this work, we fabricated zinc stannate based microcubes on glass substrates using hydrothermal method and studied its performance as gas sensor when exposed to LPG, ammonia and ethanol. The sensor attained maximum sensitivity of 63% for 3000 ppm LPG and 86% for 9300 ppm ammonia at 250ºC. The results highlighted that zinc stannate based nanomaterials can serve as potential candidates for developing LPG and ammonia sensors suitable for practical applications. We have also conducted the experiment of fabrication of ZnO nanorods based sensor on Alumina substrates. Silver inks (silver nanoparticle based colloid) was used to form the electrodes of the sensor. Electroless nickel plating of silver was also performed to prevent silver from dissolving during the growth process of ZnO nanorods. The sensor response was tested for different concentration of LPG, ammonia and ethanol. The sensor exhibited a maximum sensitivity of 63% for 9300 ppm ammonia and 36% for 10000 ppm LPG at 250ºC. |
| Year | 2010 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. ME-10-02 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Industrial Systems Engineering (DISE) |
| Academic Program/FoS | Microelectronics (ME) |
| Chairperson(s) | Dutta, Joydeep |
| Examination Committee(s) | Hornyak, Gabor L. ;Chanchana Thanachayanont; |
| Scholarship Donor(s) | Asian Institute of Technology Fellowship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2010 |