The days of self-assembling nanoparticles taking hours to form a film over a microscopic-sized wafer are over. Researchers with the U.S. Department of Energy (DOE)'s Lawrence Berkeley National Laboratory (Berkeley Lab) have devised a technique whereby self-assembling nanoparticle arrays can form a highly ordered thin film over macroscopic distances in one minute.
Ting Xu, a polymer scientist with Berkeley Lab's Materials Sciences Division, led a study in which supramolecules based on block copolymers were combined with gold nanoparticles to create nanocomposites that under solvent annealing quickly self-assembled into hierarchically-structured thin films spanning an area of several square centimeters. The technique is compatible with current nanomanufacturing processes and has the potential to generate new families of optical coatings for applications in a wide number of areas including solar energy, nanoelectronics and computer memory storage. This technique could even open new avenues to the fabrication of metamaterials, artificial nanoconstructs that possess remarkable optical properties.
"Our technique can rapidly generate amazing nanoparticle assemblies over areas as large as a silicon wafer," says Xu, who also holds a joint appointment with the University of California (UC) Berkeley's Departments of Materials Sciences and Engineering, and Chemistry. "You can think of it as pancake batter that you can spread over a griddle, wait one minute and you have a pancake ready to eat."To read more, click here.