Periodically ordered nanohetero inorganic structures of nanoparticles, nanorods and layers in a matrix from self-assembled block copolymers. Issue 1706 (9th September 2014)

• Record Type: Journal Article
• Authors: Wakayama, Hiroaki; Yonekura, Hirotaka; Kawai, Yasuaki
• Editors: Cao, C.
• Is Part Of: MRS proceedings. Issue 1706:(2014)
• Publication Date: 2014-09-09
• Subjects: self-assembly, -- nanostructure, -- magnetic properties; Electrical engineering -- Congresses; Physics -- Congresses; Materials -- Research -- Congresses; Materials science -- Congresses; 620.11
• DOI: 10.1557/opl.2014.855
• Languages: English
• ISSNs: 0272-9172

Abstract

ABSTRACT: Periodically ordered nanohetero inorganic structures offer great promise due to their unique electric, ionic, magnetic, and photonic properties. Many studies have focused on the formation of periodically ordered nano-hetero inorganic structures through layer-by-layer adsorption, sputtering, and self-assembly methods. However, the construction of three-dimensional periodically ordered nanohetero inorganic structures with desired sizes and morphologies remains a great challenge. We present a simple method for producing three-dimensional periodically ordered inorganic nanoheterostructures with controlled shape and size by replicating self-assembled block copolymers (BCPs) containing precursors of metals and metal oxides. Precursors were dissolved with BCPs in a solvent. Upon evaporation of the solvent, each precursor was selectively introduced into a separate polymer block. Application of an external magnetic field (10 T) to the BCP-precursor composites resulted in a phase transition of from spheres to hexagonal cylinders. Subsequent pyrolytic removal of the BCPs produced periodically ordered nanoheterostructures that were structural replicates of the precursor–BCP composites. Self-assembled nano-hetero inorganic structures of nanoparticles, nanorods and layers in a matrix were produced. The morphology and domain size can be tailored by controlling the molecular weight and relative block length of block copolymers. The controlled size and morphology of the inorganic nanoheterostructures demonstrate the method's utility for producing highly functional materials.