Strain Effect in Palladium Nanostructures as Nanozymes
Strain Effect in Palladium Nanostructures as Nanozymes
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DOI：
10.1021/acs.nanolett.9b03782
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发表时间：
2020-01-01
期刊：
影响因子：
10.8
通讯作者：
Xia, Xiaohu
中科院分区：
文献类型：
--
作者：
Xi, Zheng;Cheng, Xun;Xia, Xiaohu
虽然已经研究了各种物理化学参数（如尺寸，面，组成和内部结构）对纳米酶（即纳米级酶模拟物）催化效率的影响，但菌株效应从未被报道和理解。本文以具有过氧化物酶样活性的Pd八面体和二十面体为模型系统，研究了菌株对纳米酶的影响。结果表明，负载型二十面体钯的过氧化物酶样催化效率是负载型八面体钯的2倍。理论分析表明，拉伸应变比压缩应变更有利于OH自由基（催化的关键中间体）的生成。二十面体比八面体更有活性，因为二十面体放大了表面应变场。作为概念验证演示，将张力Pd二十面体应用于生物标志物的免疫分析，其性能优于未张力Pd八面体和天然过氧化物酶。本研究结果可为指导高效纳米酶的设计提供坚实的基础。
While various effects of physicochemical parameters (e.g., size, facet, composition, and internal structure) on the catalytic efficiency of nanozymes (i.e., nanoscale enzyme mimics) have been studied, the strain effect has never been reported and understood before. Herein, we demonstrate the strain effect in nanozymes by using Pd octahedra and icosahedra with peroxidase-like activities as a model system. Strained Pd icosahedra were found to display 2-fold higher peroxidase-like catalytic efficiency than unstrained Pd octahedra. Theoretical analysis suggests that tensile strain is more beneficial to OH radical (a key intermediate for the catalysis) generation than compressive strain. Pd icosahedra are more active than Pd octahedra because icosahedra amplify the surface strain field. As a proof-of-concept demonstration, the strained Pd icosahedra were applied to an immunoassay of biomarkers, outperforming both unstrained Pd octahedra and natural peroxidases. The findings in this research may serve as a strong foundation to guide the design of high-performance nanozymes.