Figure 4

The evidence of the retarded evaporation. a, b, c and d are the TEM images taken at the heating temperatures of 310, 350,400 and 450 °C, respectively. One can find the growth of the cavity inside the particle. The evaporation rate estimated from the images agrees to the estimation from the bulk value of heat of vaporization. Assuming the particle radius of 65 nm and the evaporation rate of, the influence of the evaporation on the TD is assessed, resulting in the round-dot curve (irradiation + evaporation) and the box curve (only irradiation) in (e). The x axis of test temperature means the heating temperature