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论文类型：期刊论文

发表时间：2011-07-01

发表刊物：CHEMISTRY-A EUROPEAN JOURNAL

收录刊物：SCIE、EI

卷号：17

期号：30

页面范围：8434-8439

ISSN号：0947-6539

关键字：carbon; co-oxidation; gold; nanocasting; yolk-shell materials

摘要：The use of nanostructured yolk-shell materials offers a way to discriminate support and particle-size effects for mechanistic studies in heterogeneous catalysis. Herein, gold yolk-shell materials have been synthesized and used as model catalysts for the investigation of support effects in CO oxidation. Carbon has been selected as catalytically inert support to study the intrinsic activity of the gold nanoparticles, and for comparison, zirconia has been used as oxidic support. Au, @C materials have been synthesized through nanocasting using two different nonporous-core@mesoporous-shell exotemplates: Au@SiO2@ZrO2 and Au@SiO2@m-SiO2. The catalytic activity of Au, @C with a gold core of about 14 nm has been evaluated and compared with Au, @ZrO2 of the same gold core size. The strong positive effect of metal oxide as support material on the activity of gold has been proved. Additionally, size effects were investigated using carbon as support to determine only the contribution of the nanoparticle size on the catalytic activity of gold. Therefore, Au, @C with a gold core of about 7 nm was studied showing a less pronounced positive effect on the activity than the metal oxide support effect.