Investigation of the Structure and Interface Features of Ni/Ce1- xZrxO2Catalysts for CO and CO2Methanation

V. P. Pakharukova, D. I. Potemkin, O. A. Stonkus, N. A. Kharchenko, A. A. Saraev, A. M. Gorlova

Research output: Contribution to journalArticlepeer-review

Abstract

The structural features and reduction-induced structural evolution of Ni/Ce1-xZrxO2 catalysts for the methanation of carbon oxides were investigated. The catalysts prepared by the impregnation technique were investigated by ex situ and in situ X-ray diffraction (XRD) analysis, atomic pair distribution function (PDF) analysis, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), and temperature-programmed reduction by H2. The main part of nickel was established to exist on the support surface as bulk NiO and Ni0 nanoparticles in as-prepared and reduced under reaction conditions catalysts, respectively. The metal-support interaction with incorporation of Ni2+ ions into the Ce1-xZrxO2 crystal lattice was also revealed. In situ XRD and XPS studies allowed one to monitor the structural evolution of the Ni/Ce1-xZrxO2 catalysts during their heating under H2 atmosphere in the temperature range of 25-450 °C. The formation of Ni0 nanoparticles was shown to favor reduction of Ce1-xZrxO2 oxide via hydrogen spillover. In situ XRD results revealed reversible expansion and contraction of the Ce1-xZrxO2 crystal lattice in reductive and oxidative atmospheres, which are associated with Ce4+ ↔ Ce3+ transitions and redistributions of oxygen vacancies. The elucidated metal-support interaction and synergism of redox properties of the Ni/Ce1-xZrxO2 catalysts are relevant for high activity in the CO2 and CO methanation reactions.

Original languageEnglish
Pages (from-to)20538-20550
Number of pages13
JournalJournal of Physical Chemistry C
Volume125
Issue number37
Early online date10 Sep 2021
DOIs
Publication statusPublished - 23 Sep 2021

OECD FOS+WOS

  • 2.05 MATERIALS ENGINEERING
  • 1.07 OTHER NATURAL SCIENCES
  • 1.04 CHEMICAL SCIENCES

Fingerprint

Dive into the research topics of 'Investigation of the Structure and Interface Features of Ni/Ce<sub>1- x</sub>Zr<sub>x</sub>O<sub>2</sub>Catalysts for CO and CO<sub>2</sub>Methanation'. Together they form a unique fingerprint.

Cite this