Synthesis and Characterization of Graphite Intercalation Compounds with Sulfuric Acid

Abstract

In this work, graphite intercalation compounds (GICs) were synthesized using three different oxidizers: (NH4)2S2O8, K2S2O8, and CrO3 with and without P2O5 as a water-binding agent. Furthermore, the samples obtained were heat-treated at 800 °C. Specimens were characterized by optical microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), and scanning electron microscopy (SEM). The correlation between different characteristic parameters of the Raman analysis has shown that the use of CrO3 results in a much higher structural disorder compared to the products obtained using persulfate oxidizers. Narrowing the correlation set revealed that minimal defect concentration can be reached by using K2S2O8, while the use of (NH4)2S2O8 causes a slightly higher concentration of defects. It was also established that the additional use of P2O5 can help to achieve more effective intercalation and has a positive effect on the formation of the stage I GIC phase. After heat treatment, the intercalated products mostly return to a graphite-like structure; however, the samples obtained with CrO3 stand out with the most significant changes in their surface morphology. Therefore, analysis suggests that GICs obtained using persulfate oxidizers and P2O5 could be a candidate to produce high-quality graphene or graphene oxide.

A Combined Raman Spectroscopy and Atomic Force Microscopy System for In Situ and Real-Time Measures in Electrochemical Cells

“…By exploiting the non-contact mode, we can compare chemical maps and phase-contrast and morphological images. As an example, here we report the correlation between the G i peak (located at around 1605 cm −1 –1610 cm −1 [ 35 ] and characteristic of intercalated HOPG [ 32 ]) and some special areas that are observed in the phase-contrast images after the exposure of the graphite electrode to a relatively intense laser beam. Figure 6 , acquired at a constant potential of 300 mV after CV, depicts a comparison between the map of the G i peak intensity (a), the AFM phase-contrast image (b), the D peak map (c), and the electrode surface morphology (d).…”

Surface modification of Polyether-ether-ketone for enhanced cell response: a chemical etching approach

“…Further, these sulfonic groups introduce additional oxygen atoms, altering oxygen’s overall weight concentration, which was further confirmed by the EDX results that showed a higher weight % of oxygen in the treatment groups ( Ha et al, 1997 ). In addition, sulfuric acid is a strong oxidizing agent and can lead to the oxidation and degradation of the polymer chains ( Rimkute et al, 2022 ). Oxygen from the sulfuric acid molecule can react with the polymer’s carbon and hydrogen atoms, causing them to break down into smaller molecules.…”

Biomass Pyrolysis-Derived Biochar: A Versatile Precursor for Graphene Synthesis

“…The obtained biochar from pyrolysis of the B-WC/O sample was collected after the treatment, and thereafter, its modifications by the Hummmers method [18] and intercalation with persulfate salts [19,35] were attempted in order to obtain a graphene-like material. In order to inspect the structural and morphological properties, as well electronic conductivity, all three materials, pristine biochar and those modified by two types of aforementioned methods, were thoroughly analyzed.…”