Easy Access to Metallic Copper Nanoparticles with High Activity and Stability for CO Oxidation

Autor(es)

Goncalves, Renato V. ^[1] ; Wojcieszak, Robert ^{[2, 3]} ; Wender, Heberton ^[4] ; Dias, Carlos Sato B. ^[5] ; Vono, Lucas L. R. ^[1] ; Eberhardt, Dario ^[6] ; Teixeira, Sergio R. ^[7] ; Rossi, Liane M. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, BR-05508000 Sao Paulo - Brazil

^[2] Univ Lille Nord France, F-59000 Lille - France

^[3] UMR CNRS 8181, UCCS, F-59655 Villeneuve Dascq - France

^[4] Univ Fed Mato Grosso do Sul, Inst Fis, BR-79070900 Campo Grande, MS - Brazil

^[5] LNLS, BR-13083970 Sao Paulo - Brazil

^[6] Univ Caxias Sul, BR-95700000 Bento Goncalves, RS - Brazil

^[7] Univ Fed Rio Grande do Sul, Inst Fis, BR-90046900 Porto Alegre, RS - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ACS APPLIED MATERIALS & INTERFACES; v. 7, n. 15, p. 7987-7994, APR 22 2015.
• Citações Web of Science: 26

Resumo

Copper catalysts are very promising, affordable alternatives for noble metals in CO oxidation; however, the nature of the active species remains unclear and differs throughout previous reports. Here, we report the preparation of 8 nm copper nanoparticles (Cu NPs), with high metallic content, directly deposited onto the surface of silica nanopowders by magnetron sputtering deposition. The as-prepared Cu/SiO2 contains 85% Cu-0 and 15% Cu2+ and was enriched in the Cu phase by H-2 soft pretreatment (96% Cu-0 and 4% Cu2+) or further oxidized after treatment with O-2 (33% Cu-0 and 67% Cu2+). These catalysts were studied in the catalytic oxidation of CO under dry and humid conditions. Higher activity was observed for the sample previously reduced with H-2, suggesting that the presence of Cu-metal species enhances CO oxidation performance. Inversely, a poorer performance was observed for the sample previously oxidized with O-2. The presence of water vapor caused only a small increase in the temperature require for the reaction to reach 100% conversion. Under dry conditions, the Cu NP catalyst was able to maintain full conversion for up to 45 h at 350 degrees C, but it deactivated with time on stream in the presence of water vapor. (AU)

• Processo FAPESP: 11/17402-9 - Desenvolvimento de nanopartículas magnéticas multifuncionais para terapia do câncer
• Beneficiário: Heberton Wender Luiz dos Santos
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 14/15159-8 - Nanopartículas metálicas: desafios na preparação, estabilização e ativação para catálise
• Beneficiário: Liane Marcia Rossi
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 13/21323-2 - Desenvolvimento de nanocatalisadores avançados de níquel e cobre altamente eficientes na produção de gás de síntese pela reação reversa de deslocamento gás-água (RWGS)
• Beneficiário: Renato Vitalino Gonçalves
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado