Self-Standing Reduced Graphene Oxide Papers Electrodeposited with Manganese Oxide Nanostructures as Electrodes for Electrochemical Capacitors

Free‐Standing N‐doped Reduced Graphene Oxide Papers Decorated with Iron Oxide Nanoparticles: Stable Supercapacitor Electrodes

“…Reduction of the GO paper with hydrazine vapor resulted in the formation of foam-like N-rGO paper, as previously reported. [32] Effects of chemical reduction duration and thermal annealing on the morphology and the thickness of N-rGO paper are presented in the cross-sectional FESEM images ( Figure 1). While chemically reduced papers are similar in terms of thickness (Figures 1 a-c), thermal annealing results in the formation of more compact layers and a decrease in the thickness of N-rGO paper (Figures 1 d-f).…”

“…The peaks around 285.2, 286.2, and 287.6 eV correspond to CÀ N, CÀ O, and C=O bonds, respectively. [32,38] The CÀ O and C=O peaks originate from the remaining oxygen functional groups of N-rGO structure (where hydroxy/epoxy and carbonyl/carboxyl groups respectively contribute to CÀ O and C=O signals). [33] CÀ N peak, on the other hand, results from the N-doping in the N-rGO structure.…”

“…A single peak centered around 400.0 eV was observed in all the N1s spectra, which is a characteristic pyrazoline group peak, formed as a result of hydrazine reduction. [32,39] The N1s peak binding energy did not change after thermal treatment ( Figure S2d-f), indicating that the thermal reduction was ineffective in terms of producing new nitrogen-including species. The relative peak intensities of functional groups normalized to CÀ C/C=C/CÀ H peak are given in Table 2.…”

“…Graphene oxide solution was synthesized via a modified Hummers' method as previously reported. [32,60] To obtain self-standing GO papers, 10 ml of 3 g L À 1 GO solution was filtered via a vacuumassisted filtration system. To reduce GO papers, the chemical reduction was performed with hydrazine monohydrate using different reduction times: 6, 10, and 24 h and these were named as N-rGO 6 , N-rGO 10 , and N-rGO 24 , respectively.…”

First‐Row Transition‐Metal Cations (Co2+, Ni2+, Mn2+, Fe2+) and Graphene (Oxide) Composites: From Structural Properties to Electrochemical Applications

“…Synthesis of graphene oxide:G raphene oxide used in this study was synthesized by am odified Hummers method, which was reported earlier. [43,59] Briefly,g raphite was oxidized with NaNO 3 and KMnO 4 in ice-cold concentrated H 2 SO 4 solution. The obtained powder (graphite oxide) was sonicated for several hours to obtain exfoliated graphene oxide (GO) solution.…”