Li Ming, associate professor, Hubei University: synthesis of two-dimensional conjugated covalent organic framework films based on Suzuki polymerization at the interface

Introduction at present, the two-dimensional conjugated covalent organic framework (2d-ccof) films are mainly prepared by the formation of reversible covalent bonds such as Schiff base bond (C = n) or boron oxygen bond (B-O), which makes the synthesized materials easy to degrade and low stability The synthesis of 2d-ccof films based on highly stable C-C bond is one of the Holy Grails in this field Although there have been some sporadic reports, the adaptability of this method is very low Recently, the research group of Liming associate professor of Hubei University has made a breakthrough in the field of 2d-ccof film research, revealing a method to synthesize 2d-ccof film (or two-dimensional conjugated polymer) based on Suzuki polymerization on the oil-water interface This method is easy to operate, mild in conditions, wide in applicability, and easy to obtain raw materials It can be used to synthesize various two-dimensional homopolymers and two-dimensional copolymers, and has important originality and application prospects Relevant research results were published in angelw Chem Int ed (DOI: 10.1002 / anie 201811399) Brief introduction of Liming associate professor research group the current work of the research group includes: synthesis of two-dimensional materials (two-dimensional polymer film materials, two-dimensional supramolecular film materials, two-dimensional covalent organic framework and two-dimensional metal organic framework, etc.) and application of such materials in electronics, energy, environmental protection, etc In addition, the research group has also been involved in polymer hydrogel materials, pharmaceuticals and chemical industry Li Ming, associate professor, School of chemistry and chemical engineering, Hubei University, Chutian student He received his bachelor's degree from Huazhong University of science and technology in 2006, his master's degree from Tsinghua University in 2009 and his doctor's degree from Zurich Federal University of technology in 2013 From 2013 to 2014, he was engaged in postdoctoral research in Max Planck Institute of polymer in Germany In 2014, he joined Hubei University and was promoted to associate professor in 2015 He has published more than 10 papers as the first author or corresponding author in international SCI journals such as J am Chem SOC., angelw Chem Int ed., chem SCI., small, chem EUR J., and applied for 8 invention patents Cutting edge research achievements: Based on Suzuki polymerization, c-c-bonded 2D conjugated covalent organic framework films are synthesized on the interface Liming group of Hubei University has done a series of pioneering work in the field of 2D materials (chem EUR J., 2018, 24, 16440; chem SCI., 2018, 9, 5912; small, 2017, 13, 1604077; org Electron, 2017, 49, 174), and recently made a breakthrough in the field of two-dimensional conjugated covalent organic framework film research, proposed a method to synthesize 2d-ccof film on the oil-water interface based on Suzuki polymerization The proposed synthesis method opens the door to the general synthesis of 2d-ccof films based on C-C bond Firstly, the mechanism of Suzuki reaction is analyzed, and it is found that Suzuki reaction system can be divided into oil phase and water phase; in the whole reaction cycle, the metal transfer process can only occur on the interface, and the process is reversible Based on the above analysis, the author deduced the feasibility and specific implementation method of Suzuki polymerization for the synthesis of 2d-ccof film: firstly, the oil-soluble monomer and catalyst are dissolved in the oil phase, and the alkali is dissolved in the water; then the two phases are placed in the same reaction vessel and left in the refrigerator for a period of time, that is, 2d-ccof film can be generated on the oil-water interface (Figure 1) Fig 1: (a) Suzuki reaction; (b) synthesis of 2d-ccof through Suzuki reaction on the interface; and (c) reversible reaction during metal transfer (source: angelw Chem Int ed.) based on this method, we have successfully prepared porous graphene film (2dccof1) and 2d-ccof 2 (2dccof2) with porphyrin structure from commercialized monomer and one-step synthesized monomer respectively (Fig 2) Then, 2dccof1 was proved by OM, AFM, SEM, Raman, IR, XPS, UV-Vis, FL and HRTEM And 2dccof2 (Fig 3 and 4) Fig 2: interface synthesis of 2dccof1 (a) and photos under ultraviolet light (365 nm) (b); interface synthesis of 2dccof2 (c) and photos under normal light (d) (source: angel Chem Int e D.) Fig 3: om image (a), AFM image (b), SEM image (c), Raman spectrum (d), IR spectrum (E), XPS spectrum (f), UV Vis and FL spectrum (g) and HRTEM image (H-J) of 2dccof1 (source: angel Chem Int e D.) Figure 4: om image (a), AFM image (b), SEM image (c), HRTEM image (d), Raman spectrum (E), IR spectrum (f), XPS spectrum (g), UV-vis and FL spectrum (H) of 2dccof2 (source: angelw Chem Int ed.) in order to prove the application value of 2d-ccof based on C-C bond, the author used porous graphene as channel material to prepare field effect transistor (FET), and found that the transistor has three orders of magnitude higher carrier mobility than the transistor based on 2d-ccof based on C = n bond In addition, we also found that the porous graphene can be used as the catalyst for hydrogen production from water cracking, and its catalytic effect is similar to that of N or p-doped graphene These applications will provide ideas for the development of new FET channel materials and noble metal free her catalysts This achievement was recently published in angew Chem Int ed (DOI: 10.1002 / anie 201811399) The first author of this paper is Zhou Deng and Tan Xianyang, master students of Hubei University, and the corresponding author is associate professor Liming of Hubei University The above research work was supported by the National Natural Science Foundation of China (21873027, 21504023) Nowadays, people and scientific research have been paid more and more attention in the economic life China has ushered in the "node of science and technology explosion" Behind the progress of science and technology is the work of countless scientists In the field of chemistry, in the context of the pursuit of innovation driven, international cooperation has been strengthened, the influence of Returned Scholars in the field of R & D has become increasingly prominent, and many excellent research groups have emerged in China For this reason, CBG information adopts the 1 + X reporting mechanism CBG information, chembeangoapp, chembeango official microblog, CBG wechat subscription number and other platforms jointly launch the column of "people and scientific research", approach the domestic representative research group, pay attention to their research, listen to their stories, record their demeanor, and explore their scientific research spirit.