Probing the Gold Nanorod−Ligand−Solvent Interface by Plasmonic Absorption and Thermal Decay

Thermal transport between CTAB passivated gold nanorods and solvent is studied by an optical pump−probe technique. Increasing the free CTAB concentration from 1 mM to 10 mM causes a ∼3× increase in the CTAB layer’s effective thermal interface conductance and a corresponding shift in the longitudinal surface plasmon resonance. The transition occurs near the CTAB critical micelle concentration, revealing the importance of the role of free ligand on thermal transport.