Figure 2. Experiments with Milli-Q water droplets performed using the CRAFT.

(a) Images of the droplets during a freezing experiment. (b) Fraction of the droplets frozen (f_frozen) as a function of temperature during freezing experiments. The data were obtained from three different experiments. Also shown is a classical nucleation theory-based parameterization for homogeneous freezing of 5 μL pure water droplets with a cooling rate of 1 °C/min (ref. ³²). (c) Fraction of the droplets frozen as a function of temperature during a melting experiment with a heating rate of 0.1 °C/min.