Perpendicularly Aligned, Anion Conducting Nanochannels in Block Copolymer Electrolyte Films

Abstract

Connecting structure and morphology to bulk transport properties, such as ionic conductivity, in nanostructured polymer electrolyte materials is a difficult proposition because of the challenge to precisely and accurately control order and the orientation of the ionic domains in such polymeric films. In this work, poly(styrene-block-2-vinylpyridine) (PSbP2VP) block copolymers were assembled perpendicularly to a substrate surface over large areas through chemical surface modification at the substrate and utilizing a versatile solvent vapor annealing (SVA) technique. After block copolymer assembly, a novel chemical vapor infiltration reaction (CVIR) technique selectively converted the 2vinylpyridine block to 2-vinyl n-methylpyridinium (NMP + X − ) groups, which are anion charge carriers. The prepared block copolymer electrolytes maintained their orientation and ordered nanostructure upon the selective introduction of ion moieties into the P2VP block and post ion-exchange to other counterion forms (X − = chloride, hydroxide, etc.). The prepared block copolymer electrolyte films demonstrated high chloride ion conductivities, 45 mS cm −1 at 20 °C in deionized water, the highest chloride ion conductivity for anion conducting polymer electrolyte films. Additionally, straight-line lamellae of block copolymer electrolytes were realized using chemoepitaxy and density multiplication. The devised scheme allowed for precise and accurate control of orientation of ionic domains in nanostructured polymer electrolyte films and enables a platform for future studies that examines the relationship between polymer electrolyte structure and ion transport.

Self‐Assembly Behavior of an Oligothiophene‐Based Conjugated Liquid Crystal and Its Implication for Ionic Conductivity Characteristics

“…The ionic conductivity of 4T/PEO4‐LiTFSI thin films is measured by EIS using interdigitated gold electrodes devices (IDEs) as shown in Figure a. IDEs are used in order to enhance signal‐to‐noise ratio in highly resistive thin films . Due to the geometry of IDE, the ionic conductivity reported in our work is in‐plane conductivity, or conductivity in the direction parallel to the substrate.…”

Cation–dipole interaction that creates ordered ion channels in an anion exchange membrane for fastOH−conduction

“…One of the most efficient synthetic strategies is to selectively attach cationic groups onto a specific segment in block or graft copolymers via multi-step reactions. [17][18][19][20][21][22] The polarity mismatch between the ionic and neutral segments provides the main driving force for aggregation of ionic moieties (termed ion clusters). 23,24 These ion Jianjun Zhang and Yubin He authors contributed equally to this work.…”

Characterizing the Interface Scaling of High χ Block Copolymers near the Order–Disorder Transition

“…Block copolymers (BCPs) offer intriguing possibilities 1 as templates for patterning membranes, 2–4 metal oxides, 5,6 and other lithographically useful structures. 7–10 The most commonly studied BCPs offer accessibility to feature size and domain period (pitch) length scales between 20 and 100 nm.…”