Wang Hui, Zhao Wei, Zhao Yang, Xu Cong-Hui, Xu Jing-Juan, Chen Hong-Yuan
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Anal Chem. 2020 Oct 20;92(20):14006-14011. doi: 10.1021/acs.analchem.0c02913. Epub 2020 Sep 30.
Single particle plasmon scattering can provide real-time imaging information on the synthesis of nanomaterials. Here, an electrochemical deposition strategy is reported to synthesize plasmonic Au@Metal core-shell nanoparticles (Au@M NPs), which exhibit localized surface plasmon resonance (LSPR) properties. Because of the excellent catalytic activity of the methanol oxidation reaction (MOR), Pt, Pd, and Rh were reduced on the surface of Au NPs to form monometallic and bimetallic shells. Under dark field microscopy (DFM), the scattering changes could be utilized to track the surface nucleation and bulk deposition process. The synthesized Au@M NPs, which combined the plasmonic and electrocatalytic features, showed greatly enhanced activity for MOR. Under LSPR excitation, the electroxidation process toward MOR was accelerated and increased approximately linearly with increased illumination intensity, which could be mostly attributed to the generation of energetic charge carriers. This strategy of real-time plasmonic tracking electrochemical deposition at the single particle level is facile and universal, which could be extended to the precise synthesis of other plasmonic core-shell nanomaterials and the investigation of the pathway of plasmon accelerated chemical conversion.
单粒子等离子体散射能够提供有关纳米材料合成的实时成像信息。在此，报道了一种电化学沉积策略来合成等离子体金@金属核壳纳米粒子（Au@M NPs），其具有局域表面等离子体共振（LSPR）特性。由于甲醇氧化反应（MOR）具有优异的催化活性，铂、钯和铑在金纳米粒子表面被还原，形成单金属和双金属壳层。在暗场显微镜（DFM）下，散射变化可用于跟踪表面成核和体相沉积过程。合成的Au@M NPs结合了等离子体和电催化特性，对MOR表现出大大增强的活性。在LSPR激发下，MOR的电氧化过程加速，且随着光照强度的增加近似呈线性增加，这主要归因于高能电荷载流子的产生。这种在单粒子水平实时等离子体跟踪电化学沉积的策略简便且通用，可扩展到其他等离子体核壳纳米材料的精确合成以及等离子体加速化学转化途径的研究。
