Nanostructured iron oxide catalysts with gold for the oxidation of carbon monoxide

• Tipo: Artigo em Revista Científica Internacional
• Data: 2012

Autores

S.A.C. Carabineiro (Autor) FEUP; N. Bogdanchikova (Autor) Outra; P.B. Tavares (Autor) Outra; J. L. Figueiredo (Autor) FEUP

Revista

Título: RSC Advances

Vol. 2 Nº 7

Páginas: 2957-2965

ISSN: 2046-2069

Editora: Royal Society of Chemistry

Indexação

ISI Web of Science

Scopus

Classificação Científica

FOS: Ciências da engenharia e tecnologias > Engenharia química

CORDIS: Ciências Físicas > Química > Catálise heterogénea

Outras Informações

Abstract (EN): A commercial iron oxide support is compared with Fe2O3 samples prepared by decomposition of iron nitrate, at 300 uC and 500 uC and heating times varying from 30 min to 96 h in N2. Different methods were used for gold deposition, namely double impregnation (DIM), liquid phase reductive deposition (LPRD) and ultrasonication (US). Samples were characterised by N2 adsorption at 2196 uC, high resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and temperature programmed reduction. CO oxidation was used as a test reaction to compare the catalytic activities. The best results were obtained for the sample produced by decomposition of nitrate at 300 uC for 1 h, which showed the largest surface area and highest amount of hydroxylated iron species. Increasing the calcination time and/or the temperature produced less active samples. Although LPRD materials showed the smallest gold nanoparticle sizes (1–12 nm), the best catalytic results were obtained for the DIM materials. This is most likely related to the oxidation state of gold (Au+) found in the DIM catalysts, in contrast with LPRD and US materials, where metallic gold (Au0) is present. Other samples showed lower activities. Nevertheless, all samples prepared by DIM had better catalytic activity than the Au/Fe2O3 World Gold Council reference catalyst

Idioma: Inglês

Tipo (Avaliação Docente): Científica