In‐Situ Observation of Nanoparticle Formation Under Different Power of Microwave Irradiation

Microwave technology has emerged as one of the useful methods for nanoparticle synthesis. Despite many studies on this area, its underlying mechanism has not been clearly understood. In this study, in‐situ observation of nanoparticle growth was carried out and the profiles and behaviors of produced bubbles and particles under microwave effect were reported. Sizes of bubble and nanoparticle particle were measured during and after microwave irradiation using a DLS apparatus and behavior of particle growth and superheating effect were observed. From the experimental data, it is apparent that the maximum bubble sizes were greatly influenced by the irradiation power and solute concentration. Particle number density, which is related to the initial solute concentration, is also an important factor for the bubble size produced during the irradiation. Finally, through in‐situ observation of superheating effect, the behavior was frequently caused by the irradiation at higher power. To prevent superheating effect, influencing factors such as the irradiation power and number density should be controlled to ensure a stable operation of particle formation process. The sizes of bubbles and nanoparticles were measured during and after microwave irradiation using a DLS apparatus. The maximum bubble sizes were greatly influenced by the irradiation power and solute concentration, which are related to the particle number density. To prevent superheating effect, the irradiation power and number density should be controlled, to ensure a stable operation of the particle formation process.