Acta Phys. -Chim. Sin. ›› 2017, Vol. 33 ›› Issue (2): 393-398.doi: 10.3866/PKU.WHXB201611033

• ARTICLE • Previous Articles     Next Articles

Identifying the Hydrogen Bonding Patterns of Melamine and Melem Self-Assemblies on Au(111) Surface

Li WANG1,He-Xia SHI1,Wen-Yuan WANG1,Hong SHI1,Xiang SHAO1,2,*()   

  1. 1 Department of Chemical Physics, CAS Key Laboratory of Urban Pollutant Conversion, University of Science and Technology of China, Hefei 230026, P. R. China
    2 Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, P. R. China
  • Received:2016-10-28 Published:2017-01-12
  • Contact: Xiang SHAO
  • Supported by:
    the National Natural Science Foundation of China(91227117,21333001,91545128)


Melamine and melem molecules are widely used precursors for synthesizing graphitic carbon nitride (g-C3N4), the latter also a hot two-dimensional material with photocatalytic applications. The molecular structures of both are respectively identical to the repeating units of two distinct g-C3N4 phases. In this work, the adsorption and self-assembly of melamine and melem on an Au(111) surface were investigated with low-temperature scanning tunneling microscopy (STM). Particularly, the patterns of hydrogen bonds (HBs) in their assemblies were identified and compared. It was found that melamine can only form one type of HB and two kinds of assembly structures, whereas melem can form three types of HBs and six kinds of assembly structures in total. Moreover, the involved HBs can be transformed by tip manipulation. These findings may provide a new strategy for tuning the functionality of surface self-assemblies by manipulating intermolecular hydrogen bonds. This also paves a route for the in situ synthesis of g-C3N4 on metallic surfaces and subsequent investigations of their physicochemical properties.

Key words: Melamine, Melem, Au(111), Scanning tunneling microscopy, Hydrogen bond, Selfassembly