Issue 13, 2020

Photocatalyzed preferential oxidation of CO under simulated sunlight using Au–transition metal oxide–sepiolite catalysts

Abstract

In the present study a series of Au–transition metal oxides supported on a clay mineral such as sepiolite were tested in the preferential oxidation of CO in an excess of H2 under simulated solar light irradiation and in the absence of light, at 30 °C and atmospheric pressure. Transition metal oxides (ZnO, Fe2O3, NiO, MnO2, and Co3O4) were dispersed over the sepiolite surface where, subsequently, Au nanoparticles with an average particle size between 2 and 3 nm were successfully deposited–precipitated. The obtained photocatalysts were characterized by XRD, XRF, DRUV-Vis, N2 adsorption–desorption and HRTEM in order to evaluate the optical, structural and chemical properties of the prepared samples. Despite the low amount of gold (nominal 1.0 wt%), the catalysts exhibited an outstanding behavior under light irradiation, with reaction rates between 4.5 and 5.2 mmol COox gcat−1 h−1 for the Au–NiSep, Au–CoSep and Au–ZnSep samples. These photocatalysts exhibited a high dispersion of the respective transition metal oxides over the sepiolite support and the presence of low-coordinated hemispherical gold nanoparticles. The superior photocatalytic efficiency of these samples was ascribed to the reduction of the electron–hole pair recombination of photogenerated charge carriers by the excitation of the localized surface plasmon resonance of the Au nanoparticles. The BET surface area and the gold particle size seemed to be relevant factors affecting the catalytic performance.

Graphical abstract: Photocatalyzed preferential oxidation of CO under simulated sunlight using Au–transition metal oxide–sepiolite catalysts

Article information

Article type
Paper
Submitted
02 nov 2019
Accepted
27 dec 2019
First published
30 dec 2019

Dalton Trans., 2020,49, 3946-3955

Photocatalyzed preferential oxidation of CO under simulated sunlight using Au–transition metal oxide–sepiolite catalysts

E. Rodríguez Aguado, J. A. Cecilia, A. Infantes-Molina, A. Talon, L. Storaro, E. Moretti and E. Rodríguez-Castellón, Dalton Trans., 2020, 49, 3946 DOI: 10.1039/C9DT04243A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements