Figure 1. Boiling characteristics of RGO colloid and time history of the heat flux and wall temperature on the SiO₂ heater.

(a) Boiling curve, which is characterized by the heat flux and wall temperature, shows the water and RGO colloid boiling. At the maximum heat flux (CHF), the wall temperature in water boiling increases rapidly, however, it in RGO colloid boiling increases very slowly. (b) Wall temperature of RGO colloid boiling increases very slowly with time after heat flux reaches the CHF. The margin of time can provide the assurance of more effective and safer heat transfer condition near CHF.