文摘
We report experimental studies of interfacial heat transport for a system of Au nanodisks supported on fused silica substrates, coated by hydrophilic and hydrophobic self-assembled monolayers, and immersed in water–ethanol mixtures and solutions of a nonionic surfactant, hexyl-β-d-glucoside in water. The Au nanodisks are abruptly heated by a sub-picosecond optical pulse; time-resolved changes in the temperature of the Au nanodisk and the liquid near the nanodisk/liquid interface are monitored by measurements of transient changes in optical transmission. The interface thermal conductance G of nanodisks coated with a hydrophilic self-assembled monolayer (SAM) of sodium 3-mercapto-1-propanesulfonate varies over the range 90 < G < 190 MW m–2 K–1 as the composition of the liquid mixture is changed from pure ethanol to pure water. With increasing hexyl-β-d-glucoside concentration in water, the interface thermal conductance of hydrophilic nanodisks decreases from 190 MW m–2 K–1 to 130 MW m–2 K–1 as the concentration is varied between pure water and 100 mM glucoside. For hydrophobic surfaces, G = 70 ± 10 MW m–2 K–1. We relate changes in thermal conductance to changes in work of adhesion.