Pattern‐Potential‐Guided Growth of Textured Macromolecular Films on Graphene/High‐Index Copper

Abstract

Macromolecular films are crucial functional materials widely used in the fields of mechanics, electronics, optoelectronics, and biology, due to their superior properties of chemical stability, small density, high flexibility, and solution‐processing ability. Their electronic and mechanical properties, however, are typically much lower than those of crystalline materials, as the macromolecular films have no long‐range structural ordering. The state‐of‐the‐art for producing highly ordered macromolecular films is still facing a great challenge due to the complex interactions between adjacent macromolecules. Here, the growth of textured macromolecular films on a designed graphene/high‐index copper (Cu) surface is demonstrated. This successful growth is driven by a patterned potential that originates from the different amounts of charge transfer between the graphene and Cu surfaces with, alternately, terraces and step edges. The textured films exhibit a remarkable improvement in remnant ferroelectric polarization and fracture strength. It is also demonstrated that this growth mechanism is universal for different macromolecules. As meter‐scale graphene/high‐index Cu substrates have recently become available, the results open a new regime for the production and applications of highly ordered macromolecular films with obvious merits of high production and low cost.

Harnessing Smectic Ordering for Electric‐Field‐Driven Guided‐Growth of Surface Topography in a Liquid Crystal Polymer

“…Among all the different hybrid approaches, guided‐growth has been widely explored and proven its efficacy in fabricating surface micro/nanostructures. [ 15–36 ] The guidance can be introduced via external fields such as electric or magnetic fields, chemical potential, wettability contrast, surface topography, and electromagnetic waves (e.g., light). [ 15,27,31–35 ] Combined with the internal driving forces of materials like crystallization, a great variety of structures are generated with applications for integrated devices, conductive electrodes, optical elements, and biomedical devices.…”

“…[ 15–36 ] The guidance can be introduced via external fields such as electric or magnetic fields, chemical potential, wettability contrast, surface topography, and electromagnetic waves (e.g., light). [ 15,27,31–35 ] Combined with the internal driving forces of materials like crystallization, a great variety of structures are generated with applications for integrated devices, conductive electrodes, optical elements, and biomedical devices. [ 14,25,30,37 ] The most extensively studied guided‐growth phenomena are based on inorganic crystals, metal oxides, and carbon‐based nanomaterials.…”

“…There are only a limited number of successes reported on crystalline conductive polymers, block copolymers, and nanoparticle crystals. [ 27,32,34–36 ]…”

“…There are only a limited number of successes reported on crystalline conductive polymers, block copolymers, and nanoparticle crystals. [27,32,[34][35][36] For polymers, fabricating surface micro/nanostructures via electrohydrodynamic (EHD) instability is considered to be a promising and low-cost method. [38,39] With the guidance of patterned electrodes, nanopillars can form on the surface of an isotropic polymer film and pack into corresponding shapes.…”