Zhang Kun, Liu Yujie, Wang Yuning, Zhao Jingjing, Liu Baohong
Department of Chemistry , Shanghai Stomatological Hospital , State Key Lab of Molecular Engineering of Polymers, and Collaborative Innovation Center of Chemistry for Energy Materials , Fudan University , Shanghai 200433 , China . Email:
Chem Sci. 2018 Dec 4;10(6):1741-1745. doi: 10.1039/c8sc04496a. eCollection 2019 Feb 14.
Metal nanoparticles (NPs) with decreased sizes are promising catalysts in energy and medicine. Measuring the local reactions and simultaneously acquiring molecular insights at single small NPs, however, remain an experimental challenge. Here we report on surface-enhanced Raman spectroscopic (SERS) tracking of catalytic reactions of single 13 nm gold NPs (GNPs) . We designed spatially isolated (>1.5 μm of inter-dimer space) GNP dimers, each of which consisted of two GNPs with sizes of ∼200 and ∼13 nm, respectively. This design integrates the SERS and catalytic activities into a single entity, while eliminating the crosstalk between adjacent particles, which allows us to trace the redox-derived spectral evolution at single 13 nm GNPs for the first time. We also quantified the reaction kinetics of each individual GNP and analyzed the average behavior of multiple GNPs. There is a large variability among different particles, which underscores the significance of single particle analysis.
尺寸减小的金属纳米颗粒（NPs）在能源和医学领域是很有前景的催化剂。然而，在单个小纳米颗粒上测量局部反应并同时获得分子层面的见解仍然是一项实验挑战。在此，我们报告了对单个13纳米金纳米颗粒（GNPs）催化反应的表面增强拉曼光谱（SERS）跟踪。我们设计了空间隔离的（二聚体间间距>1.5微米）GNP二聚体，每个二聚体由两个分别大小约为200纳米和13纳米的GNP组成。这种设计将SERS和催化活性整合到一个单一实体中，同时消除了相邻颗粒之间的串扰，这使我们首次能够追踪单个13纳米GNP上氧化还原衍生的光谱演变。我们还对每个单独的GNP的反应动力学进行了量化，并分析了多个GNP的平均行为。不同颗粒之间存在很大差异，这突出了单颗粒分析的重要性。
