4 Synthetic Methods for Controlling Multiple Structural
Levels from Block Copolymer Self-Assembly
The Wiesner group utilizes a variety of synthetic strategies for nanomaterial fabrication. This section is divided into three subsections based on different mechanisms of
structure formation. Section 4.1 deals with the utilization of BCP-derived equilibrium
structures and is most relevant to the structures described in the previous section. In
Sect. 4.2, post-processing methods of BCP-derived functional nanomaterials are
introduced, leading to polycrystalline and single crystalline nanostructures with,
e.g., improved mechanical and electrical properties. Section 4.3 summarizes novel
nonequilibrium methods leading to hierarchical structure formation.
Fig. 3 Quasicrystalline structures observed in BCP SA. (a) TEM image of a 2D 12-fold quasicrystal derived from a star block copolymer (the inset shows its FFT pattern). (b) Transcribed
tiling pattern (reprinted with permission from [34]; Copyright 2010 American Physics Society).
(c) TEM image and (d, e) unit cell of the Frank-Kasper sigma phase obtained from tetra-BCP SA
(c–e reprinted with permission from [33]; Copyright 2010 AAAS)
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K. Hur and U. Wiesner