title: Large-Area Nanoparticle Films by Continuous Automated Langmuir-Blodgett Assembly and Deposition.
abstract: The operating parameters and resulting surface morphology of automated Langmuir-Blodgett deposition of monosized micrometer-scale silica colloids from an aqueous suspension are investigated. This apparatus allows continuous roll-to-roll deposition of particles into well-ordered arrays. The reproducible deposition of particle monolayers at low to moderate deposition rates at web speeds of less than 10 mm/s is possible and accurately characterized by a simple mass balance of particles deposited from solution. At faster deposition rates, Landau-Levich flow increases the film thickness such that flow instabilities hinder uniform particle deposition. A simple phase diagram outlines transitions from dispersed to multilayer coatings and from uniform to erratic deposition patterns. While the threshold of maximum deposition rate is well-defined for these conditions, changing operating parameters, particle size, and fluid viscosity and evaporation rate, the maximum speed can be increased significantly.
authors.affiliation: Department of Chemical and Biomolecular Engineering, Lehigh University , Bethlehem, Pennsylvania 18015, United States.
authors.forename: Xue
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Chemical and Biomolecular Engineering, Lehigh University , Bethlehem, Pennsylvania 18015, United States.
authors.forename: James F
authors.initials: JF
authors.lastname: Gilchrist