Strain Effect in Palladium Nanostructures as Nanozymes

作者：Zheng Xi, Xun Cheng, Zhuangqiang Gao, Mengjing Wang, Tong Cai, Michelle Muzzio, Edwin Davidson, Ou Chen, Yeonwoong Jung, Shouheng Sun, Ye Xu, Xiaohu Xia · 发表于：Nano Letters · 年份：2019 · DOI：10.1021/acs.nanolett.9b03782 · 被引用次数：140 · 研究领域：Advanced Nanomaterials in Catalysis、Nanocluster Synthesis and Applications、Advanced biosensing and bioanalysis techniques

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.