| Full text | |
| Author(s): |
da Silva, Alisson H. M.
[1]
;
Rodrigues, Thenner S.
[2]
;
da Silva, Anderson G. M.
[2]
;
Camargo, Pedro H. C.
[2]
;
Gomes, Janaina F.
[1]
;
Assaf, Jose M.
[1]
Total Authors: 6
|
| Affiliation: | [1] Univ Fed Sao Carlos, Dept Engenharia Quim, BR-13565905 Sao Carlos, SP - Brazil
[2] Univ Sao Paulo, Dept Quim Fundamental, Inst Quim, Ave Prof Lineu Prestes, 748, BR-05508000 Sao Paulo, SP - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | Journal of Materials Science; v. 52, n. 24, p. 13764-13778, DEC 2017. |
| Web of Science Citations: | 4 |
| Abstract | |
Here, we have systematically investigated how the nature of the support influenced the oxygen mobility and activities in catalysts comprised of AgPt nanoshells deposited over inorganic oxides. We first synthesized AgPt nanoshells by galvanic replacement reaction between Ag nanospheres and PtCl6 (2-) ((aq)) combined with Pt reduction using hydroquinone as an auxiliary reducing agent. The nanoshells were then supported over TiO2, Al2O3 and CeO2. Through this methodology, we prepared materials with similar metallic nanoparticle AgPt compositions (similar to 0.99 wt% Pt), sizes (43 +/- 2 nm diameter), spherical shapes, surface morphologies, number of active sites and uniform distribution over the supports, differing only in terms of the nature of the support. The oxide reduction temperature, its capability of re-oxidation and the presence of oxygen mobility were strongly dependent on the metal-support interaction between AgPt nanoshells and oxide supports. These properties have significantly influenced their catalytic performances toward the CO oxidation. At 230 A degrees C, the CO oxidation TOF was 40.4 +/- 0.4, 6.9 +/- 1, 1.4 +/- 0.8 min(-1) for AgPt/CeO2, AgPt/TiO2, AgPt/Al2O3, respectively. These differences were attributed to the concentration of oxygen vacancies in each catalyst, which presented exactly the same trend as that of the catalytic activities. Our results may have important contributions to the design of highly active metal oxide-based catalysts toward gas-phase oxidation transformations. (AU) | |
| FAPESP's process: | 15/06246-7 - Biorefinery concept applied to biological wastewater treatment plants: environmental pollution control coupled with material and energy recovery |
| Grantee: | Marcelo Zaiat |
| Support Opportunities: | Research Projects - Thematic Grants |