Aug 2026· Macromolecules· 0 citations· 41 references
Abstract
The multilevel assembly of conjugated polymers critically determines their electronic performance. However, establishing a direct correlation from molecular-level interactions to macroscopic morphology and charge transport properties remains challenging. In this work, advanced characterization techniques were employed to identify and visualize two distinct assembly processes of a representative n-type conjugated polymer, F4BDOPV-2T, in both solution and thin film states, allowing for a structural correlation between solvent affinities and assembly structures. In 1-chloronaphthalene, strong solvation of the conjugated backbones promoted sidechain-dominated growth of nanoscale assemblies and ordered lamellar packing, resulting in compact 3D cluster aggregates in solution and well-oriented, large-scale ordered crystalline grains in the solid state. Conversely, toluene favored sidechain solvation, leading to backbone-dominated assembly growth that formed fiber networks and interconnected crystalline grains. The superior grain connectivity during backbone-dominated growth outweighed the effect of smaller grain size, yielding a three-fold enhancement in electron mobility (μe = 2.05 cm2 V–1 s–1). Through real-space electron microscopy visualization, this work bridges intermolecular interactions with multilevel assembly structures of conjugated polymers, providing fundamental insights into rational solvent regulation and morphological control for high-performance organic electronics.
Self-assembly, the spontaneous organization of molecular components into ordered structures without external intervention, offers a powerful route to complex nanomaterials. Yet the molecular pathways that govern hierarchical assembly, particularly under non-equilibrium conditions, often remain poorly understood. Here we establish an integrated experimental platform that couples microfluidic control of the assembly environment with multi-scale optical and structural probes, enabling direct correlation between morphological evolution and excitonic functionality during supramolecular growth. Using this approach, we track in real time the formation of double-walled nanotubes (DWNTs) from the amphiphilic cyanine dye C8S3, a synthetic analogue of the light-harvesting chlorosomes in green sulfur bacteria. The results show that the outer nanotube structures first, while the inner nanotube follows with a delay, ultimately giving rise to electronically coupled coaxial architectures. While the principal excitonic signatures and morphological motifs emerge within minutes of self-assembly, axial elongation and orientational refinement continue over tens of hours through a nucleation-elongation mechanism. Notably, suppressing local concentration gradients through more efficient mixing abolishes DWNT formation, establishing spatial heterogeneity as a key parameter governing hierarchical self-assembly. By linking structural evolution with excitonic functionality in real time, this combined platform provides a framework for dissecting non-equilibrium pathways in supramolecular materials.
S. Krishnaswamy, Alexey V. Kuevda, M. Stuart et al.· Nanoscale· 0 citations
The controlled fabrication of amorphous materials from small organic molecules and their translation into high-performance functional materials remain long-standing challenges. Here, we introduce a multicomponent assembly strategy to developed amorphous materials from π-conjugated amino acids, offering a versatile platform for high-performance adhesive and optical applications. The incorporation of proline-based building blocks into multicomponent networks bypasses the crystallization-induced self-assembly that otherwise dominates in solution, thereby driving liquid-liquid phase separation-like pathways to yield amorphous aggregates. These aggregates exhibit exceptional thermoreversible adhesion to iron-based substrates, with their densely packed architecture facilitating rarely observed excimer emission of fluorene. Furthermore, enhanced charge-transfer interactions with 1,2,4,5-tetracyanobenzene shift the photoluminescence from indigo to green, increase the quantum yield by orders of magnitude, and transition the emission from short-lived prompt fluorescence to long-lived thermally activated delayed fluorescence. Through supercooling, amorphous glasses with high hardness and optical transparency were successfully fabricated, wherein increasing the number of components enables systematic tuning of surface roughness, wettability, quantum yield, emission wavelength, and excited-state lifetime. This work establishes a novel paradigm for synthesizing amorphous materials within multicomponent high-entropy systems, positioning amino acid and short peptide derivatives as a versatile class of biomolecular building blocks for advanced adhesive and photonic applications.
Rong Wang, Xiao Feng, Pengyao Xing· Advances in Materials· 0 citations
Understanding the relationship between material properties and supramolecular nanostructures is essential for elucidating how nanoscale molecular organizations govern macroscale photoluminescence (PL) properties. Here, we introduce a novel pyrene-based liquid crystal mesogen (Py-LCM) and systematically investigate how its molecular packing nanostructures and orientations influence photophysical material properties. Py-LCM exhibits diverse molecular packing structures depending on solvent polarity and concentration in the solution state, leading to a variety of controllable photophysical emissions. Thermodynamic and structural analyses in the solid state reveal that the formation of metastable and stable nanostructures of Py-LCM can be precisely controlled by modulating the kinetic pathway of nanoscale molecular self-assembly. Furthermore, by inducing macroscale molecular orientation, we achieve polarization-dependent photophysical emissions. Finally, we demonstrate the practical application of Py-LCM in optically encrypted systems, taking advantage of its distinct PL characteristics in both solution and solid states.
Minwoo Rim, Dong-Gue Kang, Jun-Gee Jang et al.· Small· 0 citations
Chiral assembly of achiral conjugated polymers has emerged as a new avenue to promote (opto)electronic properties and control the angular momentum of charge carriers and photons. Solvent plays a key role in chiral emergence through the lyotropic liquid crystal (LLC) assembly pathway, yet rules underpinning solvent effect remain elusive. Here, we establish a unifying framework linking solvent quality to aggregate structure and supramolecular chirality. Using redox active conjugated polymers as model systems, we reveal two types of solution aggregation: (1) β1 aggregation, defined by fibrillar structures with weak interchain coupling and torsional backbone, promotes LLC‐mediated chiral assemblies via formation of helical fibers; (2) β2 aggregation, characterized by stacked fibrils with strong interchain coupling and reduced backbone torsion, suppresses chirality. Temperature‐dependent studies show that β2 aggregates revert to β1 upon heating, thus restoring chiral assemblies. Extending to 6 conjugated polymers across 37 polymer–solvent–temperature combinations, we demonstrate the universal link between aggregate type and chiral emergence. Further, chemical doping of chiral films derived from β1 aggregates elevates electrical conductivity by up to 100‐fold across nine polymer–solvent pairs spanning a wide range of processing conditions. These findings reveal general principles for solvent‐guided chiral assembly enabling high‐performance chiral electronics, optoelectronics and spintronics.
Sanghyun Jeon, Justin Neu, Nahyun Ahn et al.· Advances in Materials· 0 citations
The lignin structure is commonly discussed using local structural descriptors obtained by NMR and related chemical analyses, whereas its nanoscale appearance under aggregation-suppressed conditions remains difficult to evaluate. In this work, we developed a polymer matrix-assisted atomic force microscopy (AFM) approach to visualize lignin-rich domains in highly dilute miscible blend thin films. Cellulolytic enzyme lignins (CELs), acetylated CELs, and dehydrogenation polymer (DHP) model lignins were dispersed in a poly(N-vinylpyrrolidone)/glycerol matrix and spin-cast on mica for AFM observation. Differential scanning calorimetry supported apparent miscibility in the relevant low-lignin composition range, while dynamic light scattering showed that CELs were broadly aggregated in dimethyl sulfoxide. Matrix dilution and thin-film fixation enabled the observation of nanoscale particulate domains with low topographic heights. The apparent domain morphology depended on the botanical origin, acetylation, and DHP structure. These results demonstrate that matrix-assisted AFM provides a thin-film-based strategy for comparing aggregation-prone lignin samples in terms of their apparent nanoscale morphology and medium-dependent association behavior.
Miho Asaoka, Yuta Miyamori, N. Katsu et al.· Langmuir· 0 citations
Redox-active conducting conjugated polymers enable a wide range of electrochemical technologies, including bioelectronics, electrochromic devices, and energy‐storage systems, where their performance is governed by the efficiency of electrochemical doping and charge transport. While backbone design defines the electronic structure, side-chain chemistry plays a critical in regulating ion uptake, swelling, redox energetics, microstructure, carrier mobility, and processability.
In this presentation, we demonstrate how side-chain polarity, length, and substitution pattern decisively govern electrochemical doping behavior and mixed ionic–electronic transport in 3,4-propylenedioxythiophene (ProDOT)-based polymers, without requiring significant changes to the conjugated backbone. By systematically varying side chains from aliphatic and oligoether to short hydroxyl and carboxylic acid functionalities, we establish direct correlations between molecular structure and oxidation onset, ion uptake, volumetric capacitance, conductivity, swelling, and mechanical stability under operando conditions. For example, in situ spectroscopic, structural (GIWAXS), and gravimetric (EQCM-D) measurements reveal that side-chain substitution alone can toggle conductivity across four orders of magnitude, while tuning side-chain length, and polarity suppresses mechanical swelling from ~300% to below 10%, drastically improving cycling stability without compromising performance.
Lastly, we will show how these design principles influence how the polymers perform as active materials in organic electrochemical transistors, electrochromic devices, and as sensors for detecting extracellular action potentials from cardiomyocytes and hippocampal neurons. The results presented aim to demonstrate that judicious side-chain engineering enables precise control over electrochemical doping and mixed conduction, providing a rational framework for designing high-performance polymers for bioelectronic sensing, electrochromism, and energy-related applications.
