Evolution of template-assisted two-dimensional porphyrin chiral grating structure by directed self-assembly using chiral second harmonic generation microscopy

• Published in: Chinese chemical letters Vol. 35; no. 10; p. 109805
• Main Authors: Yu, Changhui, Shang, Peng, Hu, Huihui, Zhang, Yuening, Qin, Xujin, Han, Linyu, Liu, Caihe, Liu, Xiaohan, Liu, Minghua, Guo, Yuan, Zhang, Zhen
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-10-2024
• Subjects: Chiral assembly; Chiral evolution; Micro-nano structure; Porphyrin; Second harmonic generation microscopy; Template-assisted self-assembly; Chiral assembly; Micro-nano structure; Second harmonic generation microscopy; Template-assisted self-assembly; Porphyrin; Chiral evolution
• ISSN: 1001-8417
• DOI: 10.1016/j.cclet.2024.109805

Directed self-assembly has been used to create micro-nano scale patterns, including chiral periodic structures of organic molecules, for potential applications in optics, photonics, metamaterials, and medical and sensing technologies. This study presents a straightforward approach for fabricating large-scale chiral grating porphyrin assemblies through template-assisted techniques. The solution of tetrakis(4-sulfonatophenyl)porphyrin (TPPS) was induced by chiral amino acids (l/d-arginine and l/d-serine) to self-assemble into highly ordered chiral grating structures with the assistance of sodium dodecyl sulfate (SDS). The structures show precise line widths (5.5 µm) and gaps (18 µm). Using in situ optical microscopy and second harmonic generation (SHG) microscopy, the chiral characteristics and dynamic evolution of the template-assisted self-assembly are investigated. It is found that the chirality of amino acids induced TPPS self-assembled into chiral structures and the liquid contraction interface significantly enhanced the chirality of the assemblies. This study is significant for understanding the mechanism of chiral evolution and designing novel micro-nano materials with predetermined chiral properties.
The porphyrin chiral grating structure was successfully fabricated by template-assisted self-assembly. The second harmonic linearly polarized light microscopy was used to characterize the porphyrin assembly structure, and the chiral sign of the porphyrin assembly was also reversed when induced by L-and D-type amino acids. [Display omitted]