文摘
Under the depletion effect of poly(acrylic acid) chains, CdSe nanoparticles coated with oleic acid ligand aggregated into clusters and self-assembled into an ordered two-dimensional hexagon-shaped array on the surface of a carbon film. Such behavior was also reproduced via dynamic density functional theory. Given the same condition, the aggregation enhancement of nanoparticles on the substrate and the ratio of hexagonal side length to vertex size in a crystal cell are similar in both experimental and theoretical sections, suggesting a reasonable interpretation of the mechanism of the disorder-to-order transition. Thereafter, the theoretical predictions reveal the range of spontaneous self-assembly, which can be directed, enhanced, or controlled by changing either nanoparticle size or interactions among nanoparticles, poly(acrylic acid), and substrate.
