Professor Zeng Zebing's research group of Hunan University has made important progress in the field of quinone benzoquinone photoelectric functional materials precisely embedded with oxygen atoms

Recently, the research group of Zeng Zebing, Professor of School of chemistry and chemical engineering, Hunan University, has made important progress in the field of quinone and benzoquinone optoelectronic molecular materials: a simple method for the preparation of linear pentacene and benzo-9-benzene derivatives with oxygen atom intercalation has been reported for the first time (Figure 1a); zigzag The edge precise oxygen doping and p-toluenedione unit control the stability and photoelectric properties of the characteristic polyene molecules, overcome the shortcomings of the high energy level of the front-line orbital or the decrease of π electron conjugation caused by doping of the traditional benzo molecules The physical properties, electronic structures and device applications of this type of compounds are systematically studied This important research result was published in J am Chem SOC (DOI: 10.1021 / JACS 8b13884) The first author is Wang Yanpei, a doctoral student Fig 1 Synthesis method (a) of oxygen embedded quinone benzol and UV-vis-NIR absorption spectrum (b) of representative compounds (source: J am Chem SOC.) Polycyclic conjugated molecules, represented by benzo derivatives, have attracted much attention in the field of chemistry and materials science Their unique physical properties make them have potential applications in the field of Opto magnetic functional molecular materials and devices However, the synthesis of large-scale benzenes is very challenging, because of the poor stability caused by the increase of the intrinsic HOMO energy level and the poor solubility caused by large-scale benzenes For this reason, the research group put forward the oxygen embedded Benzol, through the continuous incorporation of quinone p-xylene, enhance the electronic exchange between oxygen atom and π system, and effectively strengthen the intrinsic oxidation resistance of molecules Oxygen embedded quinones are prepared by one-step Friedel Crafts reaction They have definite linear topological structure and unique electronic properties (Fig 1b) For example, 1) with the increase of chain length, the number of aromatic hexamers increases, which is conducive to improving their stability; 2 ）With the increase of molecular size, the UV-vis-NIR absorption shows a classical red shift and narrow band gap; 3) the molar extinction coefficient increases with the chain length, and the charge transfer low band absorption appears in the large-scale p-9-benzene More interestingly, their cation radicals, such as (P 1-ome) • + [SBF 6] - and (n 1-ome) • + [SBF 6] - can be prepared by chemical methods and show high stability The absorption peaks of its low energy band are red shifted to 1013 nm and 1094 nm respectively, while the main absorption peaks of n 1-ome 2 + of p-9-benzene are 930 nm, so it shows rare light color effect in solution (Fig 2) In this study, the unique physical and electronic characteristics of these molecules are discussed by means of experiments (nuclear magnetic resonance, absorption spectrum, X-ray single crystal diffraction, etc.) and theoretical calculation It is also explained that these compounds can be used as p-type semiconductor transmission materials, and their ionic type plays an important role in carrier transmission Figure 2 (P 1-ome) • + [SBF 6] -, (n 1-ome) • + [SBF 6] - (a) and (n 1-ome) 2 + (b) (source: J am Chem SOC.) the research work was supported by the team of Tang benzhong academician workstation of Hunan University, Professor Wu Jishan of National University of Singapore, Professor Chang Jingjing of Xi'an University of Electronic Science and technology And Hu Yuanyuan of Hunan University At the same time, the work is supported by the National Natural Science Foundation of China and the outstanding youth fund of Hunan Natural Science Foundation.