title: Reduction and transformation of fluorinated graphene induced by ultraviolet irradiation.
abstract: The effect of ultraviolet irradiation on fluorinated graphene (FG) dispersed in toluene was investigated for the first time. The chemical and physical characteristics of FG before and after ultraviolet irradiation were analyzed by UV-vis, FTIR, XPS,EDS, oxygen flask combustion (OFC), XRD, TGA, Raman, SEM, TEM and fluorescence spectroscopy. It is found that the F/C ratio initially decreases rapidly and then slowly with irradiation time, finally to 0.179 after irradiation for 48 h. The nature of partial C-F bonds transforms from covalent to "semi-covalent" bonding in the process of irradiation. The restoration of new sp(2) clusters is fast at the early stage within 6 h of irradiation, promoting the structural rearrangement. The morphology of irradiated fluorinated graphene (iFG) is not significantly destroyed by ultraviolet while more overlapped sheets are formed due to quick defluorination. Photoluminescence (PL) properties show that "blue emission" located at 432 nm is enhanced due to the recovery of sp(2) domains. In particular, compared to non-aromatic solvents, there is a "synergistic effect" between aromatic solvents and ultraviolet in the defluorination process. FG is unstable and shows some structural transformations under ultraviolet irradiation, which can be used to tune its structure and properties.
authors: State Key Laboratory of Polymer Materials Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu, Sichuan 610065, P.R. China. lxy6912@sina.com wx19861027@163.com.
authors: Mengmeng
authors: M
authors: Ren
authors: Xu
authors: X
authors: Wang
authors: Changshuai
authors: C
authors: Dong
authors: Baoyin
authors: B
authors: Li
authors: Yang
authors: Y
authors: Liu
authors: Teng
authors: T
authors: Chen
authors: Peng
authors: P
authors: Wu
authors: Zheng
authors: Z
authors: Cheng
authors: Xiangyang
authors: X
authors: Liu