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Optimising surface d charge of AuPd nanoalloy catalysts for enhanced catalytic activity.

ABSTRACT: Understanding the catalytic mechanism of bimetallic nanocatalysts remains challenging. Here, we adopt an adsorbate mediated thermal reduction approach to yield monodispersed AuPd catalysts with continuous change of the Pd-Au coordination numbers embedded in a mesoporous carbonaceous matrix. The structure of nanoalloys is well-defined, allowing for a direct determination of the structure-property relationship. The results show that the Pd single atom and dimer are the active sites for the base-free oxidation of primary alcohols. Remarkably, the d-orbital charge on the surface of Pd serves as a descriptor to the adsorbate states and hence the catalytic performance. The maximum d-charge gain occurred in a composition with 33-50 at% Pd corresponds to up to 9 times enhancement in the reaction rate compared to the neat Pd. The findings not only open an avenue towards the rational design of catalysts but also enable the identification of key steps involved in the catalytic reactions.

SUBMITTER: Zhu X

PROVIDER: S-EPMC6441046 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Optimising surface d charge of AuPd nanoalloy catalysts for enhanced catalytic activity.

Zhu Xiaojuan X Guo Qishui Q Sun Yafei Y Chen Shangjun S Wang Jian-Qiang JQ Wu Mengmeng M Fu Wenzhao W Tang Yanqiang Y Duan Xuezhi X Chen De Wan Ying Y

Nature communications 20190329 1

Understanding the catalytic mechanism of bimetallic nanocatalysts remains challenging. Here, we adopt an adsorbate mediated thermal reduction approach to yield monodispersed AuPd catalysts with continuous change of the Pd-Au coordination numbers embedded in a mesoporous carbonaceous matrix. The structure of nanoalloys is well-defined, allowing for a direct determination of the structure-property relationship. The results show that the Pd single atom and dimer are the active sites for the base-fr ...[more]

PMID: 30926804

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Optimising surface d charge of AuPd nanoalloy catalysts for enhanced catalytic activity.

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Optimising surface d charge of AuPd nanoalloy catalysts for enhanced catalytic activity.

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