title: Restructuring transition metal oxide nanorods for 100% selectivity in reduction of nitric oxide with carbon monoxide.
abstract: Transition metal oxide is one of the main categories of heterogeneous catalysts. They exhibit multiple phases and oxidation states. Typically, they are prepared and/or synthesized in solution or by vapor deposition. Here we report that a controlled reaction, in a gaseous environment, after synthesis can restructure the as-synthesized transition metal oxide nanorods into a new catalytic phase. Co3O4 nanorods with a preferentially exposed (110) surface can be restructured into nonstoichiometric CoO1-x nanorods. Structure and surface chemistry during the process were tracked with ambient pressure X-ray photoelectron spectroscopy (AP-XPS) and environmental transmission electron microscopy (E-TEM). The restructured nanorods are highly active in reducing NO with CO, with 100% selectivity for the formation of N2 in temperatures of 250-520 °C. AP-XPS and E-TEM studies revealed the nonstoichiometric CoO1-x nanorods with a rock-salt structure as the active phase responsible for the 100% selectivity. This study suggests a route to generate new oxide catalysts.
authors.affiliation: Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana, 46556, United States.
authors.forename: Shiran
authors.initials: S
authors.lastname: Zhang
authors.forename: Junjun
authors.initials: J
authors.lastname: Shan
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhu
authors.forename: Luan
authors.initials: L
authors.lastname: Nguyen
authors.forename: Weixin
authors.initials: W
authors.lastname: Huang
authors.forename: Hideto
authors.initials: H
authors.lastname: Yoshida
authors.forename: Seiji
authors.initials: S
authors.lastname: Takeda
authors.forename: Franklin Feng
authors.initials: FF
authors.lastname: Tao