He Feng, an associate professor of chemistry at the Southern University of Science and Technology, has made important progress in the field of two-dimensional supramolecular self-assembly of polymer. His research was published in the international journal Nature Communications. The paper was entitled “Uniform Two-dimensional Square Assemblies from Conjugated Block Copolymers Driven by π-π Interactions with Controllable Sizes.” This research work was mainly completed by Dr. He Feng, postdoctoral student Han Liang (first author) and master student Meijing Wang (second author).
a) structures of block copolymer PPV-b-P2VP; b) TEM photographs of 2-D square micelles; c) laser scanning confocal microscope photos of 2-D square micelles d) Illustration of growing process of platelet 2-D square micelles of PPV-b-P2VP driven by π–π interactions.
Two-dimensional (2-D) micro- and nano-architectures are attractive because of their unique properties. However, the formation of 2-D supramolecular highly symmetrical structures with considerable control is still a major challenge. He Feng’s group present a simple approach for the preparation of regular and homogeneous 2-D fluorescent square non-crystallization micelles with conjugated diblock copolymers PPV12-b-P2VP n through a process of dissolving–cooling–aging. The scale of the formed micelles can be controlled by the ratio of PPV/P2VP blocks and the concentration of the solution. The results reveal that the micelles of PPV12-b-P2VP n initially form 1-D structures and then grow into 2-D structures in solution, and the growth is driven by intermolecular π–π interactions with the PPV12 blocks. The formation of 2-D square micelles is induced by herringbone arrangement of the molecules, which is closely related to the presence of the branched alkyl chains attached to conjugated PPV12 cores.
In this work, GIWAXS experiments and molecular dynamic simulations were respectively supported by Professor Chen Wei from Argonne National Laboratory and Professor Qian Hujun from State Key Laboratory of Supramolecular Structure and Materials, Jilin University.
The research was funded by the research funding of the Southern University of Science and Technology, the National Youth Thousands Project, the National Natural Science Foundation of China, the Natural Science Foundation of Guangdong Province, Shenzhen Peacock Team and Shenzhen Branch of Science and Technology Commission.
Dr. He Feng’s research group is committed to the designe and synthese of organic conjugated polymer materials, and their applications in directions invloved supramolecular self-assembly, organic polymer solar cells, and organic conjugated polymer optoelectronics. Since the establishment at SUSTech, the research group has published their works in leading journals, including Nat. Commun., Chem. Mater., ACS. Energy Lett., J. Mater. Chem. A and Macromolecules, and two of them were selected as the covers.