Key Laboratory for Advanced Materials and Department of Chemistry, East China University of Science and Technology , Shanghai, 200237 P. R. China.
Anal Chem. 2014 Jun 3;86(11):5513-8. doi: 10.1021/ac500785u. Epub 2014 May 12.
Gold nanoparticles (GNPs) have been widely applied in industrial catalysis and electrocatalysis. Owing to their wide variety of shapes, sizes, and compositions, a range of different catalytic properties is possible. Thus, it is important to monitor catalytic processes and their mechanisms on single GNP surfaces to avoid averaging effects in bulk systems. Therefore, a novel method based on dark-field scattering spectroscopy was developed to monitor, in real-time, the electrocatalytic oxidation of hydrogen peroxide on a single gold nanoparticle surface. The catalytic mechanism was revealed via the plasmon resonance scattering spectral shift of single gold nanorod with the elimination of bulk effect. Moreover, we found that the presence of chloride ions could block the catalytic activity of nanorods for the oxidation of H2O2. Most importantly, it was discovered that individual nanoparticles have variable properties with different spectra shifts during the catalytic process. The obtained optical signals from individual nanorods not only offer versatile information regarding the reaction but also improve the understanding of electrochemistry and the catalysis mechanism of single nanoparticles.
金纳米粒子 (GNPs) 已广泛应用于工业催化和电催化。由于其形状、尺寸和组成的多样性，可能具有一系列不同的催化性质。因此，重要的是要在单个 GNP 表面上监测催化过程及其机制，以避免在体相系统中出现平均效应。因此，开发了一种基于暗场散射光谱的新方法，以实时监测单个金纳米粒子表面上过氧化氢的电催化氧化。通过消除体相效应的单金纳米棒的等离子体共振散射光谱位移揭示了催化机制。此外，我们发现氯离子的存在可以阻止纳米棒对 H2O2 氧化的催化活性。最重要的是，发现单个纳米粒子在催化过程中具有不同的光谱位移和可变的性质。从单个纳米棒获得的光学信号不仅提供了有关反应的多种信息，而且还提高了对电化学和单个纳米粒子催化机制的理解。
