| Texto completo | |
| Autor(es): |
Coletta, Vitor C.
[1]
;
Goncalves, V, Renato
;
Bernardi, Maria I. B.
[2]
;
Hanaor, Dorian A. H.
[3]
;
Assadi, M. Hussein N.
[4]
;
Marcos, Francielle C. F.
[5]
;
Nogueira, Francisco G. E.
[6]
;
Assaf, Elisabete M.
[7]
;
Mastelaro, Valmor R.
[2]
Número total de Autores: 9
|
| Afiliação do(s) autor(es): | [1] Univ Sao Paulo, Sao Carlos Inst Phys, BR-13566590 Sao Carlos, SP - Brazil
[2] Goncalves, Renato, V, Univ Sao Paulo, Sao Carlos Inst Phys, BR-13566590 Sao Carlos, SP - Brazil
[3] Tech Univ Berlin, Chair Adv Ceram Mat, D-10623 Berlin - Germany
[4] Natl Inst Mat Sci NIMS, Ctr Green Res Energy & Environm Mat, Tsukuba, Ibaraki 3050044 - Japan
[5] Univ Sao Paulo, Dept Chem Engn, Polytech Sch, BR-05508010 Sao Paulo, SP - Brazil
[6] Univ Fed Sao Carlos, Dept Chem Engn, BR-13565905 Sao Carlos, SP - Brazil
[7] Univ Sao Paulo, Sao Carlos Inst Chem, BR-13560970 Sao Carlos, SP - Brazil
Número total de Afiliações: 7
|
| Tipo de documento: | Artigo Científico |
| Fonte: | ACS APPLIED ENERGY MATERIALS; v. 4, n. 1, p. 452-461, JAN 25 2021. |
| Citações Web of Science: | 0 |
| Resumo | |
A water-gas shift reaction (WGS) is important and widely applied in the production of H-2. Cu-modified perovskites are promising catalysts for WGS reactions in hydrogen generation. However, the structure-dependent stability and reaction pathways of such materials remain unclear. Herein, we report catalytically active Cu-modified SrTiO3 (nominally SrTi1-xCuxO3) prepared by a modified polymeric precursor method. Microstructural analysis revealed a partially segregated CuO phase in the as-prepared materials. Operando X-ray diffraction and absorption spectroscopy showed the reduction of CuO into a stable metallic phase under conditions of WGS reactions for all compositions. Among the characterized materials, the x = 0.20 composition showed the highest turnover frequency, lowest activation energy, and the highest WGS rate at 300 degrees C. According to density functional calculations, the formation of CuO is energetically less favorable compared with SrTiO3, explaining why the segregated CuO phase on the SrTiO3 surface is reduced to Cu during the catalytic reaction, while SrTiO3 remains. For x = 0.20, the size of the segregated CuO phase is optimum for facilitating the catalytic reaction. In contrast, a higher Cu content (x = 0.3) results in an aggregation of smaller CuO particles, resulting in fewer surface active sites and a net decrease in catalytic performance. (AU) | |
| Processo FAPESP: | 17/08293-8 - Projeto 14: síntese direta de metanol a partir de CO2 |
| Beneficiário: | Francielle Candian Firmino Marcos |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 15/06246-7 - Aplicação do conceito de biorrefinaria a estações de tratamento biológico de águas residuárias: o controle da poluição ambiental aliado à recuperação de matéria e energia |
| Beneficiário: | Marcelo Zaiat |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais |
| Beneficiário: | Elson Longo da Silva |
| Modalidade de apoio: | Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs |