Title: | Acetone and Toluene Gas Sensing by WO(3): Focusing on the Selectivity from First Principle Calculations |
Author(s): | Trioni MI; Cargnoni F; Americo S; Pargoletti E; Chiarello GL; Cappelletti G; |
Address: | "National Research Council of Italy, Institute of Chemical Sciences and Technologies 'Giulio Natta', Via Golgi 19, 20133 Milano, Italy. Department of Chemistry, University of Milano, Via Golgi 19, 20133 Milano, Italy" |
ISSN/ISBN: | 2079-4991 (Print) 2079-4991 (Electronic) 2079-4991 (Linking) |
Abstract: | "Sensitivity and selectivity are the two major parameters that should be optimized in chemiresistive devices with boosted performances towards Volatile Organic Compounds (VOCs). Notwithstanding a plethora of metal oxides/VOCs combinations that have been investigated so far, a close inspection based on theoretical models to provide guidelines to enhance sensors features has been scarcely explored. In this work, we measured experimentally the sensor response of a WO(3) chemiresistor towards gaseous acetone and toluene, observing a two orders of magnitude higher signal for the former. In order to gain insight on the observed selectivity, Density Functional Theory was then adopted to elucidate how acetone and toluene molecules adsorption may perturb the electronic structure of WO(3) due to electrostatic interactions with the surface and hybridization with its electronic structure. The results of acetone adsorption suggest the activation of the carbonyl group for reactions, while an overall lower charge redistribution on the surface and the molecule was observed for toluene. This, combined with acetone's higher binding energy, justifies the difference in the final responses. Notably, the presence of surface oxygen vacancies, characterizing the nanostructure of the oxide, influences the sensing performances" |
Keywords: | Density Functional Theory acetone chemiresistor gas sensing monoclinic WO3 selectivity toluene; |
Notes: | "PubMed-not-MEDLINETrioni, Mario Italo Cargnoni, Fausto Americo, Stefano Pargoletti, Eleonora Chiarello, Gian Luca Cappelletti, Giuseppe eng Switzerland 2022/08/13 Nanomaterials (Basel). 2022 Aug 5; 12(15):2696. doi: 10.3390/nano12152696" |