Continuous, laser-heated boiling experiments with silver nanofluids were conducted to identify the non-equilibrium melting behavior of silver nanoparticles in de-ionized (DI) water. Experimental results with Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS) suggest that surface melting of silver nanoparticles (which have a bulk melting point of 961°C) can occur at ambient pressure when particles are suspended in saturated, and even subcooled (e.g. < 100 °C) water due to the localized (volumetric) heat absorption. These findings are supported by calculating a temperature-dependent Hamaker constant of silver nanofluid - i.e. the interaction between interfaces (Ag-melt-water) at the melting temperature.
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