Two-Dimensional Conjugated Polymers

Two-dimensional conjugated polymer (2DCP) refers to a sheet-like monomolecular macromolecule consisting of laterally connected repeat units with end groups along all edges. Due to its unique structure, 2DCP has the advanced characteristics of polymers, porous materials and two-dimensional materials, and has become a hotspot in the research of synthetic polymers. The spatial confinement of 2DCPs triggers unique physical, chemical, electronic, and mechanical properties, as well as special surface morphologies, leading to a number of fascinating applications (e.g., thin-film electronic, nano-membranes, organic catalysis) and thus they have been intensively investigated recently.
In general, 2DCPs can be fabricated through covalent (such as C-C, C=C bonds) chemistries. The past decade has witnessed the rapid development of methodologies such as solvent thermal methods and interfacial methods (air-water and liquid-liquid), and therefore leads to macroscopic 2DCPs with excellent ordering. Despite the rapid development of 2DCPs, more fabrication strategies or technologies are required to explore novel 2DCPs with more reliable functions and applications. We have developed different methodologies (azole-mediated aldol type polycondensation and pyrylium-mediated polycondensation) to synthesize 2DCP polymers of controllable structure.

Reference:
[1] Li, S.; Ma, R.; Xu, S.; Zheng, T.; Wang, H.; Fu, G.; Yang, H.; Hou, Y.; Liao, Z.; Wu, B.; Feng, X.; Wu, L.-Z.; Li, X.-B.; Zhang, T. Two-Dimensional Benzobisthiazole-Vinylene-Linked Covalent Organic Frameworks Outperform One-Dimensional Counterparts in Photocatalysis. ACS Catal. 2023, 13, 1089-1096.
[2] Li, S.; Geng, Y.; Teng, B.; Xu, S.; Petkov, P. S.; Liao, Z.; Jost, B.; Liu, Y.; Feng, X.; Wu, B.; Zhang, T. Nature-Inspired Pyrylium Cation-Based Vinylene-Linked Two-Dimensional Covalent Organic Framework for Efficient Sunlight-Driven Water Purification. Chem. Mater. 2023, acs.chemmater.2c03083.
[3] Wang, K.; Yang, H.; Liao, Z.; Li, S.; Hambsch, M.; Fu, G.; Mannsfeld, S. C. B.; Sun, Q.; Zhang, T. Monolayer-Assisted Surface-Initiated Schiff-Base-Mediated Aldol Polycondensation for the Synthesis of Crystalline Sp ² Carbon-Conjugated Covalent Organic Framework Thin Films. J. Am. Chem. Soc. 2023, 145, 9, 5203–5210.
[4] Li, S.; Ma, R.; Xu, S.; Zheng, T.; Fu, G.; Wu, Y.; Liao, Z.; Kuang, Y.; Hou, Y.; Wang, D.; Petkov, P. S.; Simeonova, K.; Feng, X.; Wu, L.-Z.; Li, X.-B.; Zhang, T. Direct Construction of Isomeric Benzobisoxazole–Vinylene-Linked Covalent Organic Frameworks with Distinct Photocatalytic Properties. J. Am. Chem. Soc. 2022, 144, 13953-13960.
[5] Zhang, T.; Qi, H.; Liao, Z.; Horev, Y. D.; Panes-Ruiz, L. A.; Petkov, P. S.; Zhang, Z.; Shivhare, R.; Zhang, P.; Liu, K.; Bezugly, V.; Liu, S.; Zheng, Z.; Mannsfeld, S.; Heine, T.; Cuniberti, G.; Haick, H.; Zschech, E.; Kaiser, U.; Dong, R.; Feng, X. Engineering Crystalline Quasi-Two-Dimensional Polyaniline Thin Film with Enhanced Electrical and Chemiresistive Sensing Performances, Nat. Commun. 2019, 10, 4225.
[6] Zhang, T.; Hou, Y.; Dzhagan, V.; Liao, Z.; Chai, G.; Löffler, M.; Olianas, D.; Milani, A.; Xu, S.; Tommasini, M.; Zahn, D. R. T.; Zheng, Z.; Zschech, E.; Jordan, R.; Feng, X. Copper-Surface-Mediated Synthesis of Acetylenic Carbon-Rich Nanofibers for Active Metal-Free Photocathodes, Nat. Commun. 2018, 9, 1140.

Two-Dimensional Conductive Polymers

In the grand family of conductive polymers, polyaniline (PANI) has attracted considerable interest owing to its appealing electrical conductivity and diverse chemistry. Engineering two-dimensional conducting polymer films with morphological homogeneity and long-range molecular ordering is intriguing to achieve long-range charge transport for high-performance organic electronics. In this part, we present a facile route combining air-water interface and surfactant monolayer as templates to synthesize large-area quasi-two-dimensional (q2D) PANI with controllable thickness and crystallinity. The ultra-thinness in conjunction with high crystallinity render q2D PANIs outstanding anisotropic charge transport characteristics, which manifests great potential in the areas of sensors, supercapacitors and functional membranes. The synthetic method is also expected to be extended to crystalline q2D thin films of polypyrrole, polythiophene and their analogues.

Reference:
[1] Ballabio, M.; Zhang, T.; Chen, C.; Zhang, P.; Liao, Z.; Hambsch, M.; Mannsfeld, S. C. B.; Zschech, E.; Sirringhaus, H.; Feng, X.; Bonn, M.; Dong, R.; Cánovas, E.; Band‐Like Charge Transport in Phytic Acid‐Doped Polyaniline Thin Films. Adv. Funct. Mater. 2021, 31, 2105184.
[2] Zhang, T.; Qi, H.; Liao, Z.; Horev, Y. D.; Panes-Ruiz, L. A.; Petkov, P. S.; Zhang, Z.; Shivhare, R.; Zhang, P.; Liu, K.; Bezugly, V.; Liu, S.; Zheng, Z.; Mannsfeld, S.; Heine, T.; Cuniberti, G.; Haick, H.; Zschech, E.; Kaiser, U.; Dong, R.; Feng, X. Engineering Crystalline Quasi-Two-Dimensional Polyaniline Thin Film with Enhanced Electrical and Chemiresistive Sensing Performances, Nat. Commun. 2019, 10, 4225. 
[3] Liu, K.; Qi, H.; Dong, R.; Shivhare, R.; Addicoat, M.; Zhang, T.; Sahabudeen, H.; Heine, T.; Mannsfeld, S.; Kaiser, U.; Zheng, Z.; Feng, X. On-Water Surface Synthesis of Crystalline, Few-Layer Two-Dimensional Polymers Assisted by Surfactant Monolayer, Nat. Chem. 2019, 11, 994-1000.
[4] Dong, R.; Zhang, T.; Feng, X. Interface-Assisted Synthesis of 2D Materials: Trend and Challenges, Chem. Rev. 2018, 118, 6189-6235.

Two-Dimensional Polymer Brushes

Polymer brushes refer to end-tethered macromolecular chains, they can be classified into zero-dimensional (0D), one-dimensional (1D), two-dimensional (2D) and three-dimensional (3D) categories, when special macromolecular chains are tethered through central joint points, or onto other polymer chains, planar surfaces, or spherical particles, respectively. Among them, the 2D polymer brushes, inspired by nature organisms, are drawing extensive interests due to their excellent capability for tailoring the chemical and physical properties of surface and interfaces and revealed broad application prospects in widespread fields, such as anti-biofouling surfaces, anti-bacterial surfaces, surface lubrications, actuations, and electronic devices. However, despite countless efforts, no scalable, industrially relevant or commercially viable method for synthesizing 2D polymer brushes have been demonstrated to date, polymer brushes are still grown arduously in laboratories under strict environmental control. We are devoting our efforts to develop new approaches for scalable synthesis of 2D polymer brushes as well as their industrial applications.

Reference:
[1] Li, W.; Sheng, W.; Wegener, E.; Du, Y.; Li, B.; Zhang, T.; Jordan, R. Capillary Microfluidic-Assisted Surface Structuring, ACS Macro Lett. 2020, 9, 328-333.
[2] Du, Y.; Zhang, T.; Gieseler, D.; Schneider, M.; Hafner, D.; Sheng, W.; Li, W.; Lange, F.; Wegener, E.; Amin, I.; Jordan, R. Facile Fabrication of Bio-and Dual-Functional Poly(2-oxazoline) Bottle-Brush Brush Surfaces, Chem. Eur. J. 2020, 26, 2749-2753.
[3] Zhang, T.; Benetti, E. M.; Jordan, R. Surface-Initiated Cu(0)-Mediated CRP for the Rapid and Controlled Synthesis of Quasi-3D Structured Polymer Brushes, ACS Macro Lett. 2019, 8, 145-153.
[4] Zhang, T.; Liao, Z.; Sandonas, L. M.; Dianat, A.; Liu, X.; Xiao, P.; Amin, I.; Gutierrez, R.; Chen, T.; Zschech, E.; Cuniberti, G.; Jordan, R. Polymerization Driven Monomer Passage Through Monolayer Chemical Vapour Deposition Graphene, Nat. Commun. 2018, 9, 4051.