Oxidation Etching-Induced Post-Crystallization of Palladium Nanosheets for Efficient Catalytic Hydrogenation
Zhijun Huang1, Shanshan Li2, Bolong Xu2
1Beijing National Laboratory of Molecular Sciences, Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.
Abstract:
The performances of catalysts are highly dependent on their crystallinities. It is a significant challenge to successively manipulate the crystallinities of noble metal nanocatalysts due to the strong metallic bonds, especially under ambient conditions. Herein, a post-crystallization approach is developed for successive control of the crystallinity of Pd nanosheets via selective oxidation etching of the amorphous domains. This strategy can be extended to crystallize other Pd and Ru nanomaterials. By carefully modulating the crystallinity of Pd nanosheets, the time for the complete conversion of 4-nitrostyrene via hydrogenation is reduced by 20 times. Also, crystallization can turn the selectivity of the products and improve the stability of Pd nanosheets. These findings may advance the crystal engineering of metal nanomaterials for wide applications.
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