TY - JOUR
T1 - Tunable Chemical Reactivity and Selectivity of WO3/TiO2 Heterojunction for Gas Sensing Applications
AU - Galstyan, Vardan
AU - Poli, Nicola
AU - Golovanov, Viacheslav
AU - D'Arco, Annalisa
AU - Macis, Salvatore
AU - Lupi, Stefano
AU - Bolli, Eleonora
AU - Kaciulis, Saulius
AU - Mezzi, Alessio
AU - Comini, Elisabetta
N1 - Funding Information:
This work was partially sponsored by the NATO Science for Peace and Security Programme under grant No. G5634 “Advanced Electro–Optical Chemical Sensors”; the “Multi‐Messenger and Machine Learning Monitoring of SARS‐CoV‐2 for occupational health & safety” (4M SARS‐CoV‐2) project under the Special Integrative Fund for Research (FISR), Ministry of University and Research (MUR), Italy; the “Smart Cities and Communities and social innovation” project titled “SWaRM Net/Smart Water Resource Management – Networks” (MUR); the University of Brescia (grant No. 1142/202); the MSCA4Ukraine and Academy of Finland (grant No. 353861).
Publisher Copyright:
© 2022 Wiley-VCH GmbH.
PY - 2022/12
Y1 - 2022/12
N2 - Nowadays, there is a dramatically growing demand for nanocomposite materials with new functionalities for their application in chemical gas sensors and other catalytic devices. Moreover, green synthesis methods are intensively employed in the preparation of semiconductor nanostructures to reduce the hazardous effects on human health and the environment. Here the fabrication of a nanocomposite material based on WO3 and TiO2 (WO3/TiO2) with unusual electronic band alignment and novel gas sensing properties is reported. The material is synthesized by an eco-friendly process based on the water vapor-induced oxidation of tungsten/titanium metallic films. The pristine WO3 is highly sensitive to acetone, where the response of the material is enhanced by its operating temperature. Instead, WO3/TiO2 composite shows principally different sensing performance and it has a good selective response to carbon monoxide at a relatively low operating temperature. The obtained results indicate that the significant differences between the functionalities of pristine WO3 and WO3/TiO2 material can be attributed to the band alignment and the direction of charge transfer in the WO3/TiO2 heterojunction. Hence, an efficient way for the development of WO3/TiO2 nanocomposites, which can be useful for the engineering and optimization of gas sensing and catalytic properties of WO3, is presented.
AB - Nowadays, there is a dramatically growing demand for nanocomposite materials with new functionalities for their application in chemical gas sensors and other catalytic devices. Moreover, green synthesis methods are intensively employed in the preparation of semiconductor nanostructures to reduce the hazardous effects on human health and the environment. Here the fabrication of a nanocomposite material based on WO3 and TiO2 (WO3/TiO2) with unusual electronic band alignment and novel gas sensing properties is reported. The material is synthesized by an eco-friendly process based on the water vapor-induced oxidation of tungsten/titanium metallic films. The pristine WO3 is highly sensitive to acetone, where the response of the material is enhanced by its operating temperature. Instead, WO3/TiO2 composite shows principally different sensing performance and it has a good selective response to carbon monoxide at a relatively low operating temperature. The obtained results indicate that the significant differences between the functionalities of pristine WO3 and WO3/TiO2 material can be attributed to the band alignment and the direction of charge transfer in the WO3/TiO2 heterojunction. Hence, an efficient way for the development of WO3/TiO2 nanocomposites, which can be useful for the engineering and optimization of gas sensing and catalytic properties of WO3, is presented.
KW - eco-friendly synthesis
KW - gas sensor
KW - heterojunctions
KW - selectivity
KW - WO /TiO nanostructures
U2 - 10.1002/admt.202201751
DO - 10.1002/admt.202201751
M3 - Article
AN - SCOPUS:85144114765
VL - 7
IS - 12
M1 - 2201751
ER -
