Synthesis of Reduced Graphene Oxide with Adjustable Microstructure Using Regioselective Reduction in the Melt of Boric Acid: Relationship Between Structural Properties and Electrochemical Performance

Abstract

The melt of H3BO3 was used to reach a controllable reduced graphene oxide (rGO) synthesis protocol using a graphene oxide (GO) precursor. Thermogravimetric analysis and differential scanning calorimetry (TG/DSC) investigation and scanning electron microscopy (SEM) images have shown that different from GO powder, reduction of GO in the melt of H3BO3 leads to the formation of less disordered structure of basal graphene planes. Threefold coordinated boron atom acts as a scavenger of oxygen atoms during the process of GO reduction. Fourier-transform infrared (FTIR) spectra of synthesized products have shown that the complex of glycerol and H3BO3 acts as a regioselective catalyst in epoxide ring-opening reaction and suppress the formation of ketone C=O functional groups at vacancy sites. Thermal treatment at 800 °C leads to the increased concentration of point defects in the backbone structure of rGO. Synthesized materials were tested electrochemically. The electrochemical performance of these materials essentially differs depending on the preparation protocol. The highest charge/discharge rate and double-layer capacitance were found for a sample synthesized in the melt of H3BO3 in the presence of glycerol and treated at 800 °C. The effect of optimal porosity and high electrical conductivity on the electrochemical performance of prepared materials also were studied.

Spectroscopic Analyses of Changes in Photocatalytic and Catalytic Activities of Mn- and Ni-Ion Doped and Base-Treated Reduced Graphene Oxide

“…Figure 1 shows SEM images of the morphologies of rGO and the two TM@rGO composites. The rGO sample shown in Figure 1a consists of bundles, in keeping with previous reports [33][34][35]. The SEM images of the two TM@rGO sheets, in Figure 1b,c, show structural features that are different from those of rGO.…”

Low‐Thermal‐Budget Doping of 2D Materials in Ambient Air Exemplified by Synthesis of Boron‐Doped Reduced Graphene Oxide

“…Figure a illustrates the millisecond‐scale (<10 ms) optical annealing procedures used to prepare B@rGO. BA, known to promote dehydration and additional deoxygenation reactions on the GO surface at a low temperature (Figure S1, Supporting Information), [ 26,27 ] was uniformly dissolved in an aqueous GO dispersion by ultrasonication, and the obtained solution was drop‐coated on glass substrates (Figure 1a–i) and dried to afford BA crystallites uniformly distributed on pristine GO (BA@GO) (Figure S2, Supporting Information). BA@GO–coated glass substrates were placed on the IPL equipment stage and exposed to a single millisecond‐scale light pulse generated by the Xe lamp (Figure 1a–ii).…”

Synthesis and Characterization of Reduced Graphene Oxide and Their Application in Dye-Sensitized Solar Cells

“…Reduced graphene oxide are single-layered sheets derived from the chemical reduction of graphene oxide. Various synthetic routes have been reported for the synthesis of reduced graphene oxide [24][25][26][27][28]. Reduced graphene oxide possess electrical and mechanical properties similar to that of graphene and, thus, makes them versatile for a number of applications including dye-sensitized solar cells [29][30][31][32][33].…”