Syntheses and characterizations of GO/Mn3O4 Nanocomposite film electrode materials for supercapacitor applications (original) (raw)
Related papers
Journal of Sol-Gel Science and Technology, 2020
Pure Mn 3 O 4 and Mn 3 O 4 /rGO hybrid nanocomposites were synthesized by sol-gel based in situ reduction method. The structural properties of pure and nanocomposite materials were studied by XRD. The crystallite size of the Mn 3 O 4 nanoparticle was reduced in the nanocomposite as observed by XRD analysis. SEM and TEM images depict the spherical morphology of pristine Mn 3 O 4 nanoparticles and decoration of Mn 3 O 4 nanoparticle on rGO sheets. Raman spectra confirm the formation of Mn 3 O 4 /rGO nanohybrid composites as the A g mode of Mn 3 O 4 , D, and G bands of rGO were observed in the spectra. FTIR spectra confirm the presence of various functional groups of GO and the in situ reduction of GO into rGO. The electrochemical properties of the Mn 3 O 4 and Mn 3 O 4 /rGO composites were investigated by cyclic voltammetry analysis using 1 M KOH as an electrolyte. The cyclic voltammetry results show the pseudocapacitance behavior of Mn 3 O 4, whereas the hybrid nanocomposite exhibits the combined behaviors of pseudocapacitance and EDLC. The chronopotentiometry analysis demonstrated that the specific capacitance of Mn 3 O 4 /rGO nanocomposite (427 F g −1) was relatively higher than that of Mn 3 O 4 (136 F g −1) at 1 A/g. The impact of KOH electrolyte over the specific capacitance of a electrode material was comparatively analyzed with different electrolytes. The enhancement in the specific capacitance of the nanohybrid composite was attributed due to the strong electrode-electrolyte interaction of hybrid electrode material and synergetic effect of Mn 3 O 4 and rGO.
Crystals
In this work, the chemical bath deposition (CBD) technique was utilized in the synthesis of transition metals/GO nanocomposites (Co3O4/MnO2/NiO/GO) for applications in supercapacitor electrodes. The nanocomposites after characterization showed that the electrically conductive nature and wide surface area of graphene oxide (GO) accounted for its incorporation into the nanocomposites. The synergy between the nanocomposites accounts for their improved performance and stable phase. The XRD results revealed cubic, orthorhombic, cubic, and mixed phases for the Co3O4/GO (CG), MnO2/GO (MG), NiO/GO (NG), and Co3O4/MnO2/NiO/GO (CMNG), respectively; their morphologies showed platelet nanoparticles with few agglomerates, with an average particle size of 69 ± 12 nm, 37 ± 09 nm, 58 ± 36 nm, and 36 ± 08 nm, respectively. For the produced materials, electrochemical results revealed maximum specific capacitance values of 2482 F/g from cyclic voltammograms and 1280.48 F/g from the galvanometric test....
International Journal of Scientific Research in Science and Technology, 2021
Mn3O4 and its composite nanomaterials have become promising candidate as an electrode for supercapacitor devices, because of its low cost, non-toxicity, large abundance, high porosity and high capacitance values in aqueous electrolyte. Here, we systematically summarized the impact of different morphologies of Mn3O4 and its composite nanomaterials on supercapacitive performance. Many researchers synthesized various Mn3O4 and its composite nanomaterials of exceptional properties and different morphologies for energy storage. This article reviews recent efforts and developments in synthesis methods Mn3O4 and its composite nanomaterials as an electrode material in supercapacitor.
Electrochimica Acta, 2013
In this study, we have improved the capacitance of carbon based graphene oxide (GO) and metal oxide based manganese oxide (Mn 3 O 4 ) thin films by preparing thin films of GO/Mn 3 O 4 composite using simple and inexpensive successive ionic layer adsorption and reaction (SILAR) method. These prepared films are characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDAX) and BET techniques. The XRD analysis reveals the formation of GO, Mn 3 O 4 and GO/Mn 3 O 4 composite thin films and the FTIR studies disclose the characteristic chemical bonding between the respective materials. Furthermore, Raman measurements confirm the formation of GO and GO/Mn 3 O 4 composite thin films. The SEM images demonstrate that the surface structure of GO and Mn 3 O 4 thin films can be easily tuned by forming the composite of GO and Mn 3 O 4 materials leading to excellent processability of a system. The surface area of GO/Mn 3 O 4 composite (94 m 2 g −1 ) is measured by using Brunauer-Emmett-Teller (BET) technique. The supercapacitive behaviors of different electrodes are evaluated using cyclic voltammetry (CV) and galvanostatic charge-discharge techniques in 1 M Na 2 SO 4 . The specific capacitance of 344 F g −1 is achieved for GO/Mn 3 O 4 composite electrode at a scan rate of 5 mV s −1 . In addition, impedance measurements of the GO, Mn 3 O 4 and GO/Mn 3 O 4 electrodes are executed proposing that the GO/Mn 3 O 4 composite electrodes are promising materials for supercapacitor application.
Conjugated NiO‐ZnO/GO nanocomposite powder for applications in supercapacitor electrodes material
International Journal of Energy Research, 2020
The nanocomposite of NiO-ZnO/graphene oxide (GO) was synthesized for applications in supercapacitor electrodes material. GO was produced using the modified Hummers' method, and the nanocomposite of NiO-ZnO/GO was synthesized using the co-precipitation method. Thin films of nanocomposite powder were deposited on quartzite (glass) and fluorine-doped tin oxide substrates by a drop casting technique. X-ray diffraction revealed the crystallographic information of NiO-ZnO/GO nanocomposites. The surface morphology and elemental composition were studied using a scanning electron microscopy and energy-dispersive X-ray spectroscopy, respectively. The electrochemical properties were examined using cyclic voltammetry in a 1.0 M solution of Na 2 SO 4 electrolyte with a three-electrode system. Moreover, the NiO-ZnO/GO binary metal oxides nanocomposite based electrodes fabricated for supercapacitor delivered a high specific capacitance of 1690 F g −1 for 1:1/GO sample at a scan rate of 10 mV s −1 and has excellent conductivity due to reduced band gap energy range of 1.52-1.79 eV and with electrodes resistance of 0.02 Ω. The absence of semicircle in the Nyquist plot denotes low charge transfer resistance of the electrodes. The highest energy densities obtained for 1:1/GO and 2:1/ GO are 192 and 148 Wh kg −1 , respectively, while the highest power density obtained for 1:1/GO and 2:1/GO are 8.46 and 7.42 W kg −1 , respectively. Our study paves way for a facile, affordable, nontoxic, and fast way to synthesis binary transition metal oxides/GO-based electrodes material for highperformance supercapacitor.
Synthesis of NiMoO4/3D-rGO Nanocomposite in Alkaline Environments for Supercapacitor Electrodes
Crystals
Although Graphene oxide (GO)-based materials is known as a favorable candidate for supercapacitors, its conductivity needs to be increased. Therefore, this study aimed to investigate the performance of GO-based supercapicitor with new methods. In this work, an ammonia solution has been used to remove the oxygen functional groups of GO. In addition, a facile precipitation method was performed to synthesis a NiMoO4/3D-rGO electrode with purpose of using synergistic effects of rGO conductivity properties as well as NiMoO4 pseudocapacitive behavior. The phase structure, chemical bands and morphology of the synthesized powders were investigated by X-ray diffraction (XRD), Raman spectroscopy, and field emission secondary electron microscopy (FE-SEM). The electrochemical results showed that the NiMoO4/3D-rGO(II) electrode, where ammonia has been used during the synthesis, has a capacitive performance of 932 Fg−1. This is higher capacitance than NiMoO4/3D-rGO(I) without using ammonia. Furth...
Applied Sciences
MnO2 is the most favorable material in power storage due to its technological significance and potential applications in pseudocapacitance (due to various oxidative states allowing efficient charge transfer to meet energy demands), where its properties are considerably influenced by its structure and surface morphology. In the present study, a facile hydrothermal route was used to produce different phases of MnO2 (α, β, and γ) with different morphologies. The electrochemical performance of the synthesized phases was studied in aqueous sodium sulfate as an electrolyte. X-ray diffraction, UV–Vis spectroscopy, and Fourier-transform infrared spectroscopy were used to characterize the synthesized material. The surface morphology and topography were examined using field-emission scanning electron microscopy. The direct band gap of α-, β-, and γ-MnO2 was found to be 1.86 eV, 1.08 eV, and 1.68 eV, lying in the semiconducting range, further enhancing the electrochemical performance. It was f...
Hierarchical Design of rGO-PEDOT- δ-MnO2 Nanocomposite for Supercapacitors
Journal of Electronic Materials, 2019
A hierarchical strategy has been adopted for the development of ternary composites, where nanostructured d-MnO 2 has been fabricated sonochemically on a unique mesoporous binary composite made of 3,4-ethylenedioxythiophene (EDOT) and reduced graphene oxide (rGO) in order to achieve maximum loading of 89% Mn +4 oxidation state essential for high capacitance value. All composite samples have been characterized by transmission electron microscopy, x-ray diffraction, Fourier infrared spectroscopy and thermogravimetry analysis. Oxidation states of manganese have been evaluated by x-ray photoelectron spectroscopy (XPS). The charge storage mechanism in the nanocomposite materials is primarily governed by the unique mesoporous structure developed during oxidative polymerization of the EDOT and rGO in the composites. The cumulative charge accumulation reveals the storage mechanism where, the entrance of Li + ion into the mesoporous layered structure of rGO based nanocomposites during reduction followed by re-entrance of Li + ion on oxidation, is comparable to that of Li + ion adsorption/ desorption on the surface of the nanocomposites. Impedance measurements are carried out to evaluate the contribution of the pseudocapacitance over the electrical double layer capacitance. Achievement of high specific capacitance (345 F g À1) with small attenuation ($ 12%) over 1000 continuous charging/ discharging cycles, suggests that the ternary nanocomposites with 70% loading of d-MnO 2 (RGPT70M) acts as a promising candidate for the electrode materials of the supercapacitor.
Improved electrochemical performance of Mn3O4 thin film electrodes for supercapacitors
Materials Science in Semiconductor Processing, 2018
Fabrication of the Mn 3 O 4 thin film electrodes is an important area of research for the development of supercapacitors. Investigations were made to improve the electrochemical properties of the electron beam evaporated Mn 3 O 4 films. The films grown on stainless steel substrates at a substrate temperature of 473 K with subsequent annealing at 573 K for 4 h were in a single phase, which corresponds to the tetragonal structure of Mn 3 O 4 with I41/amd (141) space group. The Raman studies were also confirmed the single phase of Mn 3 O 4 films. The AFM data revealed that the surface of the films covered with dispersed vertical grains of size 36 nm with the rms surface roughness of 18 nm. The SEM image displayed the flower like growth of Mn 3 O 4 on the substrate. The films deposited at 573 K exhibited a specific capacitance of 568 F g −1 at a current density of 1 A g −1 in 1 M Na 2 SO 4 aqueous electrolyte with excellent capacitance retention of 93% even after 5000 cycles. The films annealed above 600 K were found to have mixed phases and corresponding capacitance decreased with annealing temperatures. The films annealed at 773 K exhibited only Mn 2 O 3 phase with a lower specific capacitance of 240 F g −1 .