Since the nitrogen doping of graphene can effectively reduce the surface work function, which has a large contrast difference with the intrinsic graphene region in PEEM imaging, PEEM can be used as an effective surface research method to characterize graphite with such a structure. Olefin surface.

　　Recently, the Nano and Interface Catalysis Research Group (Group 502) of Dalian Institute of Physics and Chemistry has cooperated with the Liu Zhongfan-Peng Hailin group of the School of Chemistry and Molecular Engineering of Peking University, using the newly developed deep ultraviolet laser photoelectron emission microscope (DUV-PEEM) and aberrations. The Corrected Low Energy Electron Microscope (AC-LEEM) system conducts research on the surface morphology and surface work function of the "mosaic" graphene prepared by modulation and doping, which confirms that the intrinsic graphene region and nitrogen have been successfully realized by the chemical vapor deposition method. Controlled growth of doped graphene regions. Graphene has potentially important applications in the fields of optoelectronic technology, and the construction of PN junctions is the core to realize many optoelectronic device applications. Therefore, the construction of graphene optoelectronic functional devices must achieve high controllability and uniformity under the premise of ensuring the quality of graphene. Sexually stable doping. According to the principle of modulating doping in material growth, Liu Zhongfan-Peng Hailin’s research group from the School of Chemistry and Molecular Engineering of Peking University proposed a modulated doping growth method for graphene with high mobility and controllable doping area, realizing a "mosaic" structure. Large-scale preparation of graphene PN junction materials and use them in high-performance photoelectric conversion devices. Since the nitrogen doping of graphene can effectively reduce the surface work function, which has a large contrast difference with the intrinsic graphene region in PEEM imaging, PEEM can be used as an effective surface research method to characterize graphite with such a structure. Olefin surface. The Nano and Interface Catalysis Research Group of Dalian Institute of Physics and Chemistry has used the deep ultraviolet laser PEEM system in the early stage of graphene surface chemistry (AngewChemIntEd, 2012, 51, 4856; DOI: 10.1002/anie.201200413) and graphene surface structure (NatureCommun, 2012, 3:699; doi: 10.1038/ncomms1702) and other research areas have made a series of progress. This time, he cooperated with the Liu Zhongfan-Peng Hailin group of the School of Chemistry and Molecular Engineering of Peking University and effectively carried out the research on the electronic structure of graphene surface. These works show that PEEM will be able to play an important role in the physical and chemical research of solid surfaces.