Tunable phase behaviors of diblock copolyelectrolytes under alternating electric fields: A coarse-grained molecular dynamics study

Haiyang Huo; Wanchen Zhao; Xiaozheng Duan; Zhao-Yan Sun

doi:10.1063/5.0243907

Tunable phase behaviors of diblock copolyelectrolytes under alternating electric fields: A coarse-grained molecular dynamics study

J Chem Phys. 2025 Jan 7;162(1):014902. doi: 10.1063/5.0243907.

Authors

Haiyang Huo^{1

2}, Wanchen Zhao^{2

3}, Xiaozheng Duan^{1

2}, Zhao-Yan Sun^{1

2

4}

Affiliations

¹ School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, China.
² State Key Laboratory of Polymer Physics and Chemistry & Key Laboratory of Polymer Science and Technology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
³ College of Chemistry, Jilin University, Changchun 130012, China.
⁴ Xinjiang Laboratory of Phase Transitions and Microstructures in Condensed Matters, College of Physical Science and Technology, Yili Normal University, Yining 835000, China.

PMID: 39745159
DOI: 10.1063/5.0243907

Abstract

Diblock copolyelectrolytes have significant potential in applications such as solid-state single-ion conductors, but precisely controlling their nanostructures for efficient ion transport remains a challenge. In this study, we explore the phase behavior and microphase transitions of AX BY-type diblock copolyelectrolytes under alternating electric fields using coarse-grained molecular dynamics simulations. We systematically investigate the effects of various electric field features, including unipolar and bipolar square-waves, as well as offset and non-offset sine-waves, focusing on how field strength and period influence the self-assembling morphology of the copolyelectrolytes. Under unipolar square-waves, both the lamellar and cylindrical phase regions expand, while the disordered phase regions shrink as the field strength increases. In contrast, bipolar square-waves maintain lamellar structures more robustly, with reversed stretching behavior observed in the polymer chains. As the electric field period exceeds a critical value, both waveforms converge with the results seen under constant electric fields. In addition, sine-waves induce smoother phase transitions, expanding the ordered phase regions, particularly the cylindrical phase, due to continuous field variation. We further examine the detailed structural and dynamic properties, such as mean-square displacement, polymer conformation, and chain orientation during these transitions. This work provides fundamental insights into the structural regulation of diblock copolyelectrolytes under oscillating electric fields, guiding the design of advanced polymeric electrolytes with tailored nanostructures.