Operando Investigation of WS2 Gas Sensors: Simultaneous Ambient Pressure X-ray Photoelectron Spectroscopy and Electrical Characterization in Unveiling Sensing Mechanisms during Toxic Gas Exposure.
band bending; density functional theory; gas sensing; operando spectroscopy; surface potential; Ammonia; Nitrogen Dioxide; Tungsten Compounds; Gases; Tungsten; Nitrogen Dioxide/analysis; Nitrogen Dioxide/chemistry; Tungsten Compounds/chemistry; Density Functional Theory; Pressure; Gases/analysis; Gases/chemistry; Tungsten/chemistry; Photoelectron Spectroscopy; Ammonia/analysis; Ammonia/chemistry; Ambient pressures; Band bendings; Density-functional-theory; Electrical measurement; Gas-sensors; Operando; Sensing mechanism; Toxic gas; Bioengineering; Instrumentation; Process Chemistry and Technology; Fluid Flow and Transfer Processes
Abstract :
[en] Ambient pressure X-ray photoelectron spectroscopy (APXPS) is combined with simultaneous electrical measurements and supported by density functional theory calculations to investigate the sensing mechanism of tungsten disulfide (WS2)-based gas sensors in an operando dynamic experiment. This approach allows for the direct correlation between changes in the surface potential and the resistivity of the WS2 sensing active layer under realistic operating conditions. Focusing on the toxic gases NO2 and NH3, we concurrently demonstrate the distinct chemical interactions between oxidizing or reducing agents and the WS2 active layer and their effect on the sensor response. The experimental setup mimics standard electrical measurements on chemiresistors, exposing the sample to dry air and introducing the target gas analyte at different concentrations. This methodology applied to NH3 concentrations of 100, 230, and 760 and 14 ppm of NO2 establishes a benchmark for future APXPS studies on sensing devices, providing fast acquisition times and a 1:1 correlation between electrical response and spectroscopy data in operando conditions. Our findings contribute to a deeper understanding of the sensing mechanism in 2D transition metal dichalcogenides, paving the way for optimizing chemiresistor sensors for various industrial applications and wireless platforms with low energy consumption.
Disciplines :
Chemistry
Author, co-author :
Scardamaglia, Mattia ; MAX IV Laboratory, Lund University, 22100 Lund, Sweden
Casanova-Cháfer, Juan ; Departament d'Enginyeria Electronica, Universitat Rovira i Virgili, Països Catalans 26, 43007 Tarragona, Spain ; Chimie des Interactions Plasma Surface, Institut Matériaux, Université de Mons, Place du Parc 23, 7000 Mons, Belgium
Temperton, Robert ; MAX IV Laboratory, Lund University, 22100 Lund, Sweden
Annanouch, Fatima Ezahra ; Departament d'Enginyeria Electronica, Universitat Rovira i Virgili, Països Catalans 26, 43007 Tarragona, Spain
Mohammadpour, Amin ; Koç University Tüpraş Energy Center (KUTEM), Department of Chemistry, Koç University, 34450 Istanbul, Turkey
Malandra, Gabriel; Physics Department, University of Trieste, via A. Valerio 2, 34127 Trieste, Italy
Das, Arkaprava ; Chimie des Interactions Plasma Surface, Institut Matériaux, Université de Mons, Place du Parc 23, 7000 Mons, Belgium
Alagh, Aanchal; Departament d'Enginyeria Electronica, Universitat Rovira i Virgili, Països Catalans 26, 43007 Tarragona, Spain
Arbouch, Imane ; Université de Mons - UMONS > Faculté des Sciences > Service de Chimie des matériaux nouveaux
Montoisy, Loïc; Laboratory for Chemistry of Novel Materials, Université de Mons, Place du Parc 23, 7000 Mons, Belgium
Cornil, David ; Université de Mons - UMONS > Faculté des Sciences > Service de Chimie des matériaux nouveaux
Cornil, Jérôme ; Université de Mons - UMONS > Faculté des Sciences > Service de Chimie des matériaux nouveaux
Llobet, Eduard ; Departament d'Enginyeria Electronica, Universitat Rovira i Virgili, Països Catalans 26, 43007 Tarragona, Spain
Bittencourt, Carla ; Université de Mons - UMONS > Faculté des Sciences > Service de Chimie des Interactions Plasma-Surface
Operando Investigation of WS2 Gas Sensors: Simultaneous Ambient Pressure X-ray Photoelectron Spectroscopy and Electrical Characterization in Unveiling Sensing Mechanisms during Toxic Gas Exposure.
Research Institute for Materials Science and Engineering
Funders :
Svenska Forskningsrådet Formas Vetenskapsrådet Ministerio de Ciencia e Innovación European Regional Development Fund VINNOVA Fonds De La Recherche Scientifique - FNRS Helmholtz Association Institució Catalana de Recerca i Estudis Avançats
Funding text :
We acknowledge MAX IV Laboratory for time on Beamline HIPPIE under Proposal 20210978. Research conducted at MAX IV, a Swedish national user facility, is supported by the Swedish Research Council under contract 2018-07152, the Swedish Governmental Agency for Innovation Systems under contract 2018-04969, and Formas under contract 2019-02496. A.M. is supported by a grant from the Research Stay program, an activity of the HESEB project funded from the Initiative and Networking Fund of the Helmholtz Association. Funded in part by project no. PID2022-142451OB-C21, MICIN/AEI/10.13039/501100011033/and FEDER. E.L. is supported by the Catalan Institution for Research and Advanced Studies via the 2023 Edition of the ICREA Academia Award. The work in Mons has also been supported by the Fund for Scientific Research (FRS) of FNRS within the Consortium des Equipements de Calcul Intensif (CECI) under grant 2.5020.11 and by the Walloon Region (ZENOBE Tier-1 supercomputer) under grant 1117545. C.B and J.C. are, respectively, FNRS senior researcher and FNRS research director.
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