| Title: | Operando monitoring of a room temperature nanocomposite methanol sensor |
| Author(s): | Maqbool Q; Yigit N; Stoger-Pollach M; Ruello ML; Tittarelli F; Rupprechter G; |
| Address: | "Department of Materials, Environmental Sciences and Urban Planning (SIMAU), Universita Politecnica delle Marche INSTM Research Unit, via Brecce Bianche 12 60131 Ancona Italy. Institute of Materials Chemistry TU Wien, Getreidemarkt 9/BC A-1060 Vienna Austria guenther.rupprechter@tuwien.ac.at. University Service Center for Transmission Electron Microscopy TU Wien, Wiedner Hauptstr. 8-10 1040 Vienna Austria" |
| ISSN/ISBN: | 2044-4753 (Print) 2044-4761 (Electronic) 2044-4753 (Linking) |
| Abstract: | "The sensing of volatile organic compounds by composites containing metal oxide semiconductors is typically explained via adsorption-desorption and surface electrochemical reactions changing the sensor's resistance. The analysis of molecular processes on chemiresistive gas sensors is often based on indirect evidence, whereas in situ or operando studies monitoring the gas/surface interactions enable a direct insight. Here we report a cross-disciplinary approach employing spectroscopy of working sensors to investigate room temperature methanol detection, contrasting well-characterized nanocomposite (TiO(2)@rGO-NC) and reduced-graphene oxide (rGO) sensors. Methanol interactions with the sensors were examined by (quasi) operando-DRIFTS and in situ-ATR-FTIR spectroscopy, the first paralleled by simultaneous measurements of resistance. The sensing mechanism was also studied by mass spectroscopy (MS), revealing the surface electrochemical reactions. The operando and in situ spectroscopy techniques demonstrated that the sensing mechanism on the nanocomposite relies on the combined effect of methanol reversible physisorption and irreversible chemisorption, sensor modification over time, and electron/O(2) depletion-restoration due to a surface electrochemical reaction forming CO(2) and H(2)O" |
| Notes: | "PubMed-not-MEDLINEMaqbool, Qaisar Yigit, Nevzat Stoger-Pollach, Michael Ruello, Maria Letizia Tittarelli, Francesca Rupprechter, Gunther eng England 2023/02/11 Catal Sci Technol. 2022 Dec 14; 13(3):624-636. doi: 10.1039/d2cy01395a. eCollection 2023 Feb 6" |
