title: Perovskite Nanoparticle-Sensitized Ga2O3 Nanorod Arrays for CO Detection at High Temperature.
abstract: Noble metal nanoparticles are extensively used for sensitizing metal oxide chemical sensors through the catalytic spillover mechanism. However, due to earth-scarcity and high cost of noble metals, finding replacements presents a great economic benefit. Besides, high temperature and harsh environment sensor applications demand material stability under conditions approaching thermal and chemical stability limits of noble metals. In this study, we employed thermally stable perovskite-type La(0.8)Sr(0.2)FeO3 (LSFO) nanoparticle surface decoration on Ga2O3 nanorod array gas sensors and discovered an order of magnitude enhanced sensitivity to carbon monoxide at 500 °C. The LSFO nanoparticle catalysts was of comparable performance to that achieved by Pt nanoparticles, with a much lower weight loading than Pt. Detailed electron microscopy and X-ray photoelectron spectroscopy studies suggested the LSFO nanoparticle sensitization effect is attributed to a spillover-like effect associated with the gas-LSFO-Ga2O3 triple-interfaces that spread the negatively charged surface oxygen ions from LSFO nanoparticles surfaces over to β-Ga2O3 nanorod surfaces with faster surface CO oxidation reactions.
authors.affiliation: Department of Materials Science and Engineering & Institute of Materials Science, University of Connecticut , 97 North Eagleville Road, Storrs, Connecticut 06269-3136, United States.
authors.forename: Hui-Jan
authors.initials: HJ
authors.lastname: Lin
authors.affiliation: National Energy Technology Laboratory , 626 Cochrans Mill Road, Pittsburgh, Pennsylvania 15236, United States.
authors.forename: John P
authors.initials: JP
authors.lastname: Baltrus
authors.affiliation: Department of Materials Science and Engineering & Institute of Materials Science, University of Connecticut , 97 North Eagleville Road, Storrs, Connecticut 06269-3136, United States.
authors.forename: Haiyong
authors.initials: H
authors.lastname: Gao
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology , 771 Ferst Drive, Atlanta, Georgia 30332, United States.
authors.forename: Yong
authors.initials: Y
authors.lastname: Ding
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973, United States.
authors.forename: Chang-Yong
authors.initials: CY
authors.lastname: Nam
authors.affiliation: National Energy Technology Laboratory , 626 Cochrans Mill Road, Pittsburgh, Pennsylvania 15236, United States.|Department of Materials Science and Engineering, Carnegie Mellon University , Pittsburgh, Pennsylvania 15216, United States.
authors.forename: Paul
authors.initials: P
authors.lastname: Ohodnicki
authors.affiliation: Department of Materials Science and Engineering & Institute of Materials Science, University of Connecticut , 97 North Eagleville Road, Storrs, Connecticut 06269-3136, United States.
authors.forename: Pu-Xian
authors.initials: PX
authors.lastname: Gao
keywords: catalytic effect; gas sensor; harsh environment; nanowire; semiconductor