A method for selective bromination of graphene and its use for subsequent functionalization with aromatic molecules

• Published in: Materials research express 2017-04, Vol.4 (4), p.45601
• Main Authors: Xiaorong, Zou, Yanan, Lv, Cheng-an, Tao, Hui, Zhu, Lin, Xia, Jianfang, Wang
• Format: Article
• Language: English
• Subjects: 1,3-dibromo-5,5-dimethylhydantoin; bromination; graphene; Suzuki-coupling reaction
• ISSN: 2053-1591; 2053-1591
• DOI: 10.1088/2053-1591/aa6883

A novel method for selective bromination of graphene was proposed. The reduced graphene oxide (denoted as graphene) used as the raw material, was brominated with 1,3-dibromo-5,5-dimethylhydantoin in the mixture of trifluoromethanesulfonic acid and CH2Cl2 at room temperature. The success of bromination was confirmed by x-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersive x-ray analysis, and Fourier transform-infrared spectroscopy. Moreover, it was found that the bromine concentration of the brominated graphene increased up to 10% Br/C with increasing bromination duration for the first 24 h; then the concentration unexpectedly decreased. The brominated graphene was further functionalized with 4-pyridinyl boronic acid through the Suzuki-coupling reaction. The atomic concentration of Br greatly decreased, whereas the atomic concentration of N increased significantly. This indicated that the functionalization was successful. This proposed bromination method is easy and well-suited for graphene and its derivatives. Additionally, the brominated graphene can be a starting material for constructing other graphene-based functional materials.