Development of SnO₂/PEO nanofiber gas sensor for THC detection
department or school: Applied Science, Faculty of
data provider: DSpace
degree campus: UBCO
creator: Mehrabi, Pouria
issued: 2018-04-26T18:09:00Z
issued: 2018
related degree: Master of Applied Science - MASc
degree grantor: University of British Columbia
description: This thesis presents the development of a metal oxide semiconductor (MOS) sensor for detection of volatile organic compounds (VOCs) which is of great importance in many applications involving either control of hazardous chemicals or noninvasive diagnosis. There are numerous methods for detection of VOCs where their efficacy is assessed by their sensitivity, selectivity, recovery time and portabily. Commercial MOS sensors are embedded in a housing, blocking the gas diffusion path and also limiting their application in the handheld VOC detectors. In this research, the sensor is fabricated based on tin dioxide (SnO₂)/ Poly Ethylene Oxide (PEO) using electrospinning. The sensitivity of the proposed sensor is further improved by calcination and gold doping. The gold doping of the composite nanofibers is achieved using sputtering, and the calcination is performed using a high temperature oven. The performance of the sensor with different doping thicknesses and different calcination temperatures is investigated to identify the optimum fabrication parameters resulting in high sensitivity. The results show that the sensing properties of the sensing layer, including response and recovery time, are significantly affected by the doping and calcination procedure. The optimum calcination temperature and duration are found to be 350°C and 4 hours, respectively. Also, the optimum thickness of the gold dopant is found to be 10 nm. The sensor with the optimum fabrication process is then embedded in a microchannel coated with several metallic and polymeric layers. The role of the channel is to enhance the selectivity of the sensor against different VOCs or mixtures. The performance of the sensor is compared against a commercial sensor. The comparison is performed for methanol and a mixture of methanol and Tetrahydrocannabinol (THC) which is the psychoactive element in cannabis. Segregation of the responses obtained for methanol and the mixture of methanol and THC is presented in a 3D …
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/65646
note: Development of SnO2/PEO nanofiber gas sensor for THC detection by Pouria Mehrabi B.Sc. in Aerospace and Mechanical Engineering, Amirkabir University of Technology, 2015 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF APPLIED SCIENCE in THE COLLEGE OF GRADUATE STUDIES (Mechanical Engineering) THE UNIVERSITY OF BRITISH COLUMBIA (Okanagan) April 2018 © Pouria Mehrabi, 2018 ii The following individuals certify that they have read, and recommend to the College of Graduate Studies for acceptance, a thesis/dissertation entitled: Development of SnO2/PEO nanofiber gas sensor for THC detection submitted by Pouria Mehrabi in partial fulfillment of the requirements of the degree of Master of Applied Science Dr. Mina Hoorfar, School of Engineering Supervisor Dr. Homayoun Najjaran, School of Engineering Supervisory Committee Member Dr. Thomas Johnson, School of Engineering Supervisory Committee Member Dr. Chen Feng, School of Engineering University Examiner iii Abstract This thesis presents the development of a metal oxide semiconductor (MOS) sensor for detection of volatile organic compounds (VOCs) which is of great importance in many applications involving either control of hazardous chemicals or noninvasive diagnosis. There are numerous methods for detection of VOCs where their efficacy is assessed by their sensitivity, selectivity, recovery time and portabily. Commercial MOS sensors are embedded in a housing, blocking the gas diffusion path and also limiting their application in the handheld VOC detectors. In this research, the sensor is fabricated based on tin dioxide (SnO2)/ Poly Ethylene Oxide (PEO) using electrospinning. The sensitivity of the proposed sensor is further improved by calcination and gold doping. The gold doping of the composite nanofibers is achieved using sputtering, and the calcination is performed using a high temperature oven. The performance of the sensor with different doping thicknesses and different calcinat…
has type: Thesis/Dissertation
date issued: 2018-05
is shown at: 10.14288/1.0366012
language: eng
degree discipline: Mechanical Engineering
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/65646