NANOPARTICLE AGGREGATION AND DISPERSION BEHAVIOR CONTROL FOR MATERIAL PROCESSING

Nanoparticle and nanomaterials dispersion and aggregation behavior control is one of the most important fundamental processes to apply the functional properties development of energy related devices, such as solar cell and Li ion secondary battery. Surface modification and treatment by using various surfactants and coupling agents with different molecular structure on prepared nanoparticle surfaces in aqueous solution or non-polar organic solvents were applied to control surface interaction between particles. After surface treatment on nanoparticles in suspension, if surface structure on nanoparticles was almost completely covered and modified by surfactant or coupling agent, hard aggregate or agglomerate of nanoparticles were not formed after evaporating and drying process, and surface modified nanoparticles was able to be re-dispersed into different organic solvent. Uniform nanoparticles dispersed polymer composite or electrode for solar cell and battery were prepared from the above prepared nanoparticle's suspension without aggregation. Furthermore, molecular and nanometer scaled surface structure and interaction after various modification and treatment was characterized by using a colloid probe atomic force microscope, AFM, method. Based on the measurement results, the action mechanism of surfactant and coupling agent was discussed.