Changchun Guangji developed the first case of charged organic two-dimensional porous crystal luminescent materials

Recently, the Chinese Academy of Sciences Changchun Institute of Optics and Fine Mechanics and Physics, State Key Laboratory of Photonics and Applications led by researcher Li Bin independently designed with red emission with a positive charge of ethidium bromide organic monomer in the international community For the first time, a charged organic two-dimensional porous crystal framework material is prepared, which has important application prospects in organic semiconductor devices and photoelectric sensing fields. The above findings were published on J. Am. Chem. Soc., 2016, DOI: 10.1021 / jacs.5b13490, Impact Factor 12.1, a well-known journal in international chemistry. The first author was an assistant researcher Dr. Peace, the work has been funded by the National Natural Science Foundation project.

Two-dimensional layered materials is a new type of emerging material in recent years. Especially in 2004, the discovery of single atomic layer graphene has greatly promoted the development of two-dimensional materials, making it quickly become the research frontier. However, the graphene has almost no energy gap, limiting its use in semiconductor devices. Compared with graphene, the inherent natural band gap structure of two-dimensional layered semiconductor materials makes them have great potential in the field of microelectronics and optoelectronics. Among them, two-dimensional layered organic porous crystal materials are widely used in many fields such as photoelectric sensing, organic semiconductor devices, field effect transistors and organic solar cells due to their abundant organic light emitting functional groups, adjustable photoelectron mobility and excellent photoelectric conversion properties Has a wide range of applications. However, since the monomers of the synthesized organic porous materials are mostly electrically neutral, it is a challenge to prepare the charged crystalline organic porous crystal material and adjust its conductivity to protons or electrons.

The material prepared by Li Bin's group has a nanopore structure, and its pore size can be adjusted by the balance anions in the framework. Through the cooperation with Professor Zang Hongying and Professor Zhu Guangshan of Northeast Normal University, the keggin-type heteropoly acid phosphotungstic acid is doped into the framework. Since the surface of the phosphotungstic acid is rich in oxygen sites, the material can store a large amount of water to form a network of hydrogen bonds and protons can High-speed migration through the hydrogen-bonding network dramatically increases the proton conductivity of the material. The material doped with polyacids increased the conductivity of protons by three orders of magnitude. Moreover, the nanopore structure of the material and the uneven electric field distribution on the surface of the material have a localized effect on protons and electrons. By adjusting the distribution of the electric field inside the cell, the conductivity of the material to protons can be changed. Such charged organic two-dimensional crystalline materials will have potential applications in organic semiconductor devices and photoelectric sensing.

Figure 1: (a) Optical print of ethidium bromide monomer with red emission

(b) Preparation of two-dimensional organic porous crystal material emission spectrum

Figure 2: (a) Schematic diagram of synthesis of two-dimensional organic crystal material

(b) Schematic diagram of the layered crystals of the material

Figure 3: (ac) Proton Conductivity Comparison of Materials After Doped Polyacid

(d) The activation energy of the material.

20 Vertical Grain Traction Conveyor

20 Vertical Grain Traction Conveyor,Incline Grain Conveyors,Grain Bin Conveyor,Grain Transfer Conveyor

Gongzhuling Huaxi Agricultural Machinery Manufacturing Co.LTD , https://www.tractionsprayer.com