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Imidazolate-based ZIF-8 catalysts M@ZIF-8 (M = Au NR, Au@Ag NR, or Au@PtAg NRT; NR = nanorod, NRT = nanorattle), were assembled. Au NRs acted as the core for the epitaxial growth of the Ag shell, and oxidative etching of Au@Ag NRs led to Au@PtAg NRTs with K2PtCl4 aqueous solution. All metal nanorods (MNRs) and metal nanorattles (MNRTs) were well dispersed and fully encapsulated in ZIF-8. Au@PtAg NRTs encapsulated in ZIF-8 could lead to enhanced stability and selectivity for catalytic applications, combining the advantages of ZIF-8 (tailorable porosity) with the high surface area and improved optical sensitivity of rod-shaped NRTs. The catalyst Au@PtAg@ZIF-8 exhibited efficient catalytic activity and CO selectivity for the gas-phase photoreduction of CO2 with H2O.


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Nanorattle Au@PtAg encapsulated in ZIF-8 for enhancing CO2 photoreduction to CO

Show Author's information Yuqun Su1Haitao Xu1( )Jiajia Wang1Xikuo Luo1Zhen-liang Xu1Kefu Wang2Wenzhong Wang2
State Key Laboratory of Chemical Engineering,Membrane Science and Engineering R & D Lab, Chemical Engineering Research Center, East China University of Science and Technology (ECUST), 130 Meilong Road,Shanghai,200237,China;
State Key Laboratory of High Performance Ceramics and Super Fine Microstructure,Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road,Shanghai,200050,China;

Abstract

Imidazolate-based ZIF-8 catalysts M@ZIF-8 (M = Au NR, Au@Ag NR, or Au@PtAg NRT; NR = nanorod, NRT = nanorattle), were assembled. Au NRs acted as the core for the epitaxial growth of the Ag shell, and oxidative etching of Au@Ag NRs led to Au@PtAg NRTs with K2PtCl4 aqueous solution. All metal nanorods (MNRs) and metal nanorattles (MNRTs) were well dispersed and fully encapsulated in ZIF-8. Au@PtAg NRTs encapsulated in ZIF-8 could lead to enhanced stability and selectivity for catalytic applications, combining the advantages of ZIF-8 (tailorable porosity) with the high surface area and improved optical sensitivity of rod-shaped NRTs. The catalyst Au@PtAg@ZIF-8 exhibited efficient catalytic activity and CO selectivity for the gas-phase photoreduction of CO2 with H2O.

Keywords: core–shell, imidazolate-based ZIF-8, nanorattle, noble metal catalyst, CO2 photoreduction

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Acknowledgements

Publication history

Received: 14 October 2018
Revised: 06 December 2018
Accepted: 12 December 2018
Published: 28 December 2018
Issue date: March 2019

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© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Acknowledgements

Acknowledgements

We gratefully acknowledge the financial support from the National Natural Science Foundation of China (No. 21371058).

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