Abstract
This paper reviews the important problems associated with the synthesis of metal-oxide nanocomposites, charge transfer phenomena in these composites, their conductive and sensory properties, modeling of sensory effect and the role on this sensory effect of the electronic structure of the metal oxide. The size of metal particles and temperature significantly influence the efficiency of such systems. However, the electronic interactions between the different components of the nanocomposite films play the dominant role in the exploitation of the properties of such sensory systems. Depending on the chemical nature of the analyzed gas and the electronic structure of the semiconducting metal oxides, such interactions can result in either an increase or a decrease of the sensory effect. Thus, by varying the electronic structure of the metal oxide composite sensors as well as the temperature and size of the metal-oxide nanoparticles, the inherent characteristics of the sensor can be changed and tailored for detection of various gases. Such findings clearly open up new opportunities for development of novel selective sensors.
Highlights
The rapid growth in industrial production and the attendant environmental impact have made it imperative to develop highly sensitive and selective sensors for the detection of various pollutants in the atmosphere.Conductometric chemical sensors based on nanocrystalline metal-oxide semiconductors are currently the most promising among solid-state gas detectors due to their reliability, and ease of manufacture and application
This paper reviews the important problems associated with the synthesis of metal-oxide nanocomposites, charge transfer phenomena in these composites, their conductive and sensory properties, modeling of sensory effect and the role on this sensory effect of the electronic structure of the metal oxide
By varying the electronic structure of the metal oxide composite sensors as well as the temperature and size of the metal-oxide nanoparticles, the inherent characteristics of the sensor can be changed and tailored for detection of various gases. Such findings clearly open up new opportunities for development of novel selective sensors
Summary
The rapid growth in industrial production and the attendant environmental impact have made it imperative to develop highly sensitive and selective sensors for the detection of various pollutants in the atmosphere. Conductometric chemical sensors based on nanocrystalline metal-oxide semiconductors are currently the most promising among solid-state gas detectors due to their reliability, and ease of manufacture and application. Miniaturization and low price enable their use as personal sensors. The sensitivity of such systems is manifest by the change in conductivity resulting from chemical interaction of adsorbed analyzed gas with active centers on the surface of the sensor. Previous studies on conductometric metal oxide sensors have mostly focused on systems consisting of single semiconducting metal oxide, mostly SnO2. The disadvantage of such sensors is the rather low selectivity to gases that have similar chemical characteristics, for example, various reducing gases. The following sections describe such sensors and discuss the fundamental mechanism underlying the sensory phenomena
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
