title: Chemically enhancing block copolymers for block-selective synthesis of self-assembled metal oxide nanostructures.
abstract: We report chemical modification of self-assembled block copolymer thin films by ultraviolet light that enhances the block-selective affinity of organometallic precursors otherwise lacking preference for either copolymer block. Sequential precursor loading and reaction facilitate formation of zinc oxide, titanium dioxide, and aluminum oxide nanostructures within the polystyrene domains of both lamellar- and cylindrical-phase modified polystyrene-block-poly(methyl methacrylate) thin film templates. Near-edge X-ray absorption fine structure measurements and Fourier transform infrared spectroscopy show that photo-oxidation by ultraviolet light creates Lewis basic groups within polystyrene, resulting in an increased Lewis base-acid interaction with the organometallic precursors. The approach provides a method for generating both aluminum oxide patterns and their corresponding inverses using the same block copolymer template.
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA.
authors.forename: Jovan
authors.initials: J
authors.lastname: Kamcev
authors.forename: David S
authors.initials: DS
authors.lastname: Germack
authors.forename: Dmytro
authors.initials: D
authors.lastname: Nykypanchuk
authors.forename: Robert B
authors.initials: RB
authors.lastname: Grubbs
authors.forename: Chang-Yong
authors.initials: CY
authors.lastname: Nam
authors.forename: Charles T
authors.initials: CT
authors.lastname: Black
mesh_terms: D003460:Crystallization / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D008968:Molecular Conformation; D010087:Oxides / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D046911:Macromolecular Substances; D010087:Oxides; C009495:titanium dioxide; D014025:Titanium