Size-Dependent Melting Properties of Small Tin Particles: Nanocalorimetric Measurements

For the first time, the latent heat of fusion $\Delta H_m$ for Sn particles formed by evaporation on inert substrate with radii ranging from 5 to 50 nm has been measured directly using a novel scanning nanocalorimeter. A particle-size-dependent reduction of $\Delta H_m$ has been observed. An “excluded volume” is introduced to describe the latent heat of fusion from the enhanced surface melting of small particles. Melting point depression has also been found by our nanocalorimetric technique.