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Galvanic replacement synthesis of Ag _x Au_1-x @CeO₂ (0 ≤ x ≤ 1) core@shell nanospheres with greatly enhanced catalytic performance.

ABSTRACT: A galvanic replacement strategy has been successfully adopted to design Ag _x Au_1-x @CeO₂ core@shell nanospheres derived from Ag@CeO₂ ones. After etching using HAuCl₄, the Ag core was in situ replaced with Ag _x Au_1-x alloy nanoframes, and void spaces were left under the CeO₂ shell. Among the as-prepared Ag _x Au_1-x @CeO₂ catalysts, Ag_0.64Au_0.36@CeO₂ shows the optimal catalytic performance, whose catalytic efficiency reaches even 2.5 times higher than our previously reported Pt@CeO₂ nanospheres in the catalytic reduction of 4-nitrophenol (4-NP) by ammonia borane (AB). Besides, Ag_0.64Au_0.36@CeO₂ also exhibits a much lower 100% conversion temperature of 120 °C for catalytic CO oxidation compared with the other samples.

SUBMITTER: Liu D

PROVIDER: S-EPMC5532536 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Galvanic replacement synthesis of Ag x Au1-x @CeO2 (0 ≤ x ≤ 1) core@shell nanospheres with greatly enhanced catalytic performance.

Liu Dapeng D Li Wang W Feng Xilan X Zhang Yu Y

Chemical science 20150907 12

A galvanic replacement strategy has been successfully adopted to design Ag x Au1-x @CeO2 core@shell nanospheres derived from Ag@CeO2 ones. After etching using HAuCl4, the Ag core was in situ replaced with Ag x Au1-x alloy nanoframes, and void spaces were left under the CeO2 shell. Among the as-prepared Ag x Au1-x @CeO2 catalysts ...[more]

PMID: 28808522

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