WS2 and WS2-ZnO Chemiresistive Gas Sensors: The Role of Analyte Charge Asymmetry and Molecular Size

Ullah, Farman1,2; Ibrahim, Khaled1,2; Mistry, Kissan1,2; Samad, Abdus3; Shahin, Ahmed1,2; Sanderson, Joseph4; Musselman, Kevin1,2

2023-03-01

10.1021/acssensors.2c02762

ACS SENSORS   Impact Factor & Quartile

2379-3694

We investigate the interaction of various analytes (toluene, acetone, ethanol, and water) possessing different structures, bonding, and molecular sizes with a laser-exfoliated WS2 sensing material in a chemiresistive sensor. The sensor showed a clear response to all analytes, which was significantly enhanced by modifying the WS2 surface. This was achieved by creating WS2-ZnO heterojunctions via the deposition of ZnO nanoparticles on the WS2 surface with a high-throughput, atmospheric-pressure spatial atomic layer deposition system. Water and ethanol produced a much higher response compared to acetone and toluene for both the WS2 and WS2-ZnO sensing mediums. We resolved that the charge asymmetry points in analyte molecules play a key role in determining the sensor response. High charge asymmetry points correspond to highly polar bonds (HPBs) in a neutral molecule that have a high probability of interaction with the sensing medium. Our results indicate that the polarity of the HPBs primarily dictates the interaction between the analyte and sensing medium and consequently controls the response of the sensor. Moreover, the size of the analyte molecule was found to affect the sensing response; if two molecules have the same HPBs and are exposed to the same sensing medium, the smaller molecule is likely to produce a higher and faster response. Our study provides a comprehensive picture of analyte-sensor interactions that can help in advancing semiconductor gas sensors, including those based on two-dimensional materials.

chemiresistive gas sensor WS2-ZnO heterojunction gas sensors gas-sensing mechanism 2D materials spatial atomic layer deposition

SCI

English

Others

Natural Sciences and Engineering Research Council of Canada Discovery program["RGPIN-2017-04212","RGPAS-2017-507977"] ; Canada Foundation for Innovation John R. Evans Leaders Fund[35552]

Chemistry ; Science & Technology - Other Topics

Chemistry, Multidisciplinary ; Chemistry, Analytical ; Nanoscience & Nanotechnology

WOS:000960682500001

AMER CHEMICAL SOC

Web of Science

1.Univ Waterloo, Dept Mech & Mechatron Engn, Waterloo, ON N2L 3G1, Canada
2.Univ Waterloo, Waterloo Inst Nanotechnol, Waterloo, ON N2L 3G1, Canada
3.Southern Univ Sci & Technol, Dept Mat Sci & Engn, Shenzhen 517055, Peoples R China
4.Univ Waterloo, Dept Phys & Astron, Waterloo, ON N2L 3G1, Canada

Ullah, Farman,Ibrahim, Khaled,Mistry, Kissan,et al. WS2 and WS2-ZnO Chemiresistive Gas Sensors: The Role of Analyte Charge Asymmetry and Molecular Size[J]. ACS SENSORS,2023.

Ullah, Farman.,Ibrahim, Khaled.,Mistry, Kissan.,Samad, Abdus.,Shahin, Ahmed.,...&Musselman, Kevin.(2023).WS2 and WS2-ZnO Chemiresistive Gas Sensors: The Role of Analyte Charge Asymmetry and Molecular Size.ACS SENSORS.

Ullah, Farman,et al."WS2 and WS2-ZnO Chemiresistive Gas Sensors: The Role of Analyte Charge Asymmetry and Molecular Size".ACS SENSORS (2023).