Plasmonic nanostructures, of which gold nanoparticles are the most elementary example, owe their unique properties to localized surface plasmons (LSP), the modes of free electron oscillation. LSP alter significantly electromagnetic field in the nanostructure neighborhood (i.e., near-field), which can modify the electric dipole transition rates in organic emitters. This study aims at investigating the influence of Au@SiO₂ core–shell nanoparticles on the photophysics of porphyrins covalently attached to the nanoparticles surface. Guided by theoretical predictions, three sets of gold nanoparticles of different sizes were coated with asilica layer of similar thickness. The outer silica surface was functionalized with either free-base meso-tetraphenylporphyrin or its zinc complex. Absorption and emission bands of porphyrin overlap in energy with agold nanoparticle LSP resonance that provides the field enhancement. Silica separates the emitters from the gold surface, while the gold core size tunes the energy of the LSP resonance. The signatures of weak-coupling regime have been observed. Apart from modified emission profiles and shortened S₁ lifetimes, Qband part intensity of the excitation spectra significantly increased with respect to the Soret band. The results were explained using classical transfer matrix simulations and electronic states kinetics, taking into account the photophysical properties of each chromophore. The calculations could reasonably well predict and explain the experimental outcomes. The discrepancies between the two were discussed.

等离子纳米结构，其中金纳米颗粒是最基本的例子，其独特的性质归功于局域表面等离子体 (LSP)，即自由电子振荡模式。LSP 显着改变纳米结构邻域（即近场）中的电磁场，这可以改变有机发射器中的电偶极子跃迁率。本研究旨在研究 Au@SiO ₂核壳纳米粒子对共价附着在纳米粒子表面的卟啉光物理的影响。在理论预测的指导下，三组不同尺寸的金纳米粒子涂有相似厚度的二氧化硅层。二氧化硅外表面用游离碱中观功能化-四苯基卟啉或其锌络合物。卟啉的吸收和发射带在能量上与提供场增强的金纳米粒子 LSP 共振重叠。二氧化硅将发射器与金表面分开，而金核的尺寸则调节 LSP 共振的能量。已观察到弱耦合机制的特征。除了修改的排放剖面和缩短的 S ₁寿命，激发光谱的 Qband 部分强度相对于 Soret 带显着增加。考虑到每个发色团的光物理特性，使用经典的转移矩阵模拟和电子状态动力学来解释结果。计算可以合理地预测和解释实验结果。讨论了两者之间的差异。