Synchrotron Radiation Soft X-ray Induced Reduction in Graphene Oxide Characterized by Time-Resolved Photoelectron Spectroscopy

Abstract

Synchrotron radiation soft X-ray was employed to reduce graphene oxide (GO) films in ultrahigh vacuum. The dissociation of oxygen-containing functional groups, and the formation of sp 2 C−C bonds were revealed by time-resolved in situ X-ray photoelectron spectroscopy, demonstrating the X-ray reduction of GO. The number of C−O bonds of GO exhibited an exponential decay with exposure time. The X-ray reduction rate of GO was positively correlated with the intensity of low-energy secondary electrons excited from substrates by soft X-ray, indicating the C−O bonds were dissociated by secondary electrons.

A comparative experimental and theoretical study of the mechanism of graphene oxide mild reduction by ascorbic acid andN-acetyl cysteine for biomedical applications

“…The C 1s spectra are complex peaks, as expected, and have been subjected to curve fitting in order to extract, assign and quantify the corresponding peak components. The sequence of features obtained is consistent with previous reports, 6,9,34,35 and evidences the presence and fate of the distinct C-C and C-O functionalities present at the GO surface at the different reduction steps. In all samples, these functionalities are associated with the following components: sp 2 -hybridized C atoms (284.85 eV, white), and hydroxyl (285.85 eV, green), epoxyl (287.05 eV, light cyan), carbonyl (287.85 eV, blue), and carboxyl (288.85 eV, yellow) groups.…”

“…36 In addition, in all m-rGO samples a further component is needed to account for the variation in the low-BE line shape after incubation with H 2 A and NAC. This asymmetric feature (284.55 eV, red) is related to the restoration of p-delocalized CQC bonds 6,9,34,35 upon chemical reduction of GO with the green reductants. Upon reduction with NAC, the XP spectra of the resulting m-rGO samples show several differences compared to pristine GO.…”

Effect of Electrolytic Medium on the Electrochemical Reduction of Graphene Oxide on Si(111) as Probed by XPS

“…The typical spectral contributions of GO arising in this region are those related to the carbon atoms surrounded by different chemical environments [ 40 , 76 , 77 ], attributed C=C groups with nearly localized characteristics, C–OH (hydroxyl), C–O–C (epoxyl), C=O (carbonyl, quinonyl) and COOH (carboxyl) OFGs [ 76 , 77 , 78 ] (see Table 2 ). According to Figure 4 and Table 2 , it is apparent that the dominant OFG in pristine GO was the epoxy group on the basal plane, as expected according to Hummers’ method used by the supplier for its synthesis.…”

Electrical, thermal and electrochemical properties of γ-ray-reduced graphene oxide

“…Natural products, such as vitamins, amino acids, and Lycium barbarum extract, have also been used for GO reduction [10][11]. Different types of radiation (e.g., ionizing and nonionizing) from UV light [8], microwaves [12], laser [13], plasma [14], and X-rays [15] were employed to achieve GO reduction. In 2012, Zhang et al [16] used γ-rays to reduce GO in a water/alcohol system for the first time.…”