Two dimensional layered nickel cobaltite nanosheets as an efficient electrode material for high‐performance hybrid supercapacitor

High capacitance Co-Co 3 O 4 nanocomposite thin films have been synthesized on nickel foam (NF) using cyclic voltammetry (CV), combination of cyclic voltammetry and potentiostatic (CV PS À1.4 V and CV PS +1 V), and combination of cyclic voltammetry and pulse reverse potential (CV PRP) modes of electrodeposition. X-ray diffraction (XRD) studies reveal the presence of Co and Co 3 O 4 phases for the four electrodeposition modes. The scanning electron microscope (SEM) revealed an interesting morphology correlating the electrochemical and capacitance behavior, while the energy-dispersive X-ray spectroscopy (EDX) spectra confirmed the varying quantities of Co and O in the Co-Co 3 O 4 nanocomposite thin films. The presence of Co-O bonds were also confirmed by the attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectra obtained on these films. The capacitance values of Co-Co 3 O 4composite thin films obtained by CV, CV PS À1.4 V, CV PS +1 V, and CV PRP, respectively, were found to be 1661, 1400, 1866, and 2580 F g À1 at an applied current load of 1 A g À1 , while the capacitance retentions after 500 cycles under a high current load of 20 A g À1 for the same were 85.8%, 77.8%, 87.1%, and 90.5%, respectively. The high capacitance and their retention of the electrodeposited Co-Co 3 O 4 nanocomposite thin films show potentials as high-performance supercapacitor electrode.

Section: Introductionmentioning

confidence: 99%

Specific capacitance behavior of Co‐Co ₃ O ₄ nanocomposite thin films synthesized via different electrodeposition modes

Nuamah

Noormohammed

Sarkar

2021

“…In addition, it can be noticed that there is a peak shift in the oxidation peaks toward higher potential and 33,[40][41][42] When the specific current was increased from 1 to 20 A/g, the shape of the curves obtained from the individual electrodes remained unchanged, indicating that the as-prepared electrodes have high stability. 40 Furthermore, it can be observed that the discharge times decreased with increasing specific currents in both cases. In Figure 5C as 2580 and 2800 F/g, respectively, from the GCD curves using Equation (4),…”

Section: Resultsmentioning

confidence: 98%

Supercapacitor performance evaluation of nanostructured Ag‐decoratedCo‐Co₃O₄composite thin film electrode material

Nuamah

Noormohammed

Sarkar

2022

Summary Nanostructured Ag‐decorated Co‐Co3O4 composite thin film (Ag/Co‐Co3O4) synthesized on nickel foam (NF) by a combination of cyclic voltammetry and pulse reverse potential electrodeposition modes presents higher specific capacitance and its retention. The higher specific capacitance of 2800 F/g on Ag/Co‐Co3O4/NF composite thin film in comparison with 2580 F/g on Co‐Co3O4/NF at 1 A/g is attributable to the presence of nanostructured Ag in the composite film enhancing the ionic and electronic conductivity of the material. The morphology revealed by the scanning electron microscope correlates the electrochemical and capacitance behavior while the energy‐dispersive X‐ray spectroscopy spectra confirmed the presence of Co, Ag, and O in the Ag/Co‐Co3O4/NF composite thin film. The attenuated total reflection‐Fourier transform infrared spectra obtained further confirmed the presence of Co–O bonds. The Ag/Co‐Co3O4/NF composite thin film presented an amorphous nature as revealed by the X‐ray diffraction spectra. In addition, the Ag/Co‐Co3O4/NF electrode exhibited a maximum specific energy of 69.5 Wh/kg, specific power of 6.6 kW/kg and capacitance retention of 82.6% after 1000 cycles, while the Co‐Co3O4 electrode (with no Ag) showed lower specific energy of 60.8 Wh/kg, specific power of 5.8 kW/kg, and a capacitance retention of 78.2% after 1000 cycles. Furthermore, by the incorporation of Ag, the composite electrode showed a reduction in the equivalence series resistance value from 1.5 Ω cm2 (Co‐Co3O4/NF) to 1.0 Ω cm2 (Ag/Co‐Co3O4/NF) as well as in the charge transfer resistance (Rct) from 2.86 Ω cm2 (Co‐Co3O4/NF) to 0.96 Ω cm2 (Ag/Co‐Co3O4/NF) indicating the positive influence of the presence of Ag in the film. The electrochemical evaluation indicates that a synergistic effect between Ag and Co‐Co3O4 enhances supercapacitor electrode performance.

“…These EIS results further elucidate that the ionic and electronic conductivity of the rCMO electrode are prominently influenced by the effect of abundant oxygendefect. 41,62 Based on the CVs at various scan rates, the charge storage mechanism of the rCMO electrode material can be determined according to the power-law relation 15,19 :.…”

Section: Resultsmentioning

confidence: 99%

“…where i imply response current, v denote corresponding scan rate, and both In order to further distinguish, the capacitive and diffusion contributions to the charge storage can be determined at different scan rates on account of the below expression 15,19 :…”

Section: Resultsmentioning

confidence: 99%

“…[12][13][14][15] Besides, TMOs involve Faradic redox kinetics rather than the pure electrostatic charge storage behaviour, which thus not only dramatically mounts the capacitance but also the energy density of the SCs. [16][17][18][19] In particular, the binary cobalt molybdate (CoMoO 4 ) has received tremendous attention in recent years as a perspective batterytype electrode material because of its many impressive advantages, including fast and reversible redox kinetics, high capacity, multivalence distributions, and non-toxicity. [20][21][22][23] However, their limited electroactive sites, poor intrinsic conductivity, and astonishing volume expansion depreciate the electrochemical performance.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Impact of oxygen‐defects induced electrochemical properties of three‐dimensional flower‐like CoMoO ₄ nanoarchitecture for supercapacitor applications

Sivakumar

Raj

Kulandaivel

et al. 2022

Self Cite

The rational strategy to design the well-ordered morphology of the metal oxides with defective engineering and tailoring them into specific electrode fabrication can significantly improve their electrochemical properties for high-performance energy storage systems. Herein, we adopted an effective strategy to introduce oxygen-defect into the well-ordered three-dimensional flower-like CoMoO 4 nanoarchitecture. The Co-Mo precursor leads to the introduction of oxygendefects into the CoMoO 4 (rCMO) nanoarchitecture during the heat-treatment under an oxygen-controlled environment (argon). The oxygen-defects in the material could facilitate abundant electroactive sites and intrinsically enhance the conductivity and supercapacitor performance. The oxygen-defect CoMoO 4 (rCMO) exhibits a specific capacity of 531 mAh g À1 at a current density of 1 A g À1 compared to the pristine CoMoO 4 (CMO; ambient atmosphere) of 322 mAh g À1 under the same current density. Meanwhile, the fabricated hybrid supercapacitor (HSC) of rCMO//AC provides a maximum specific capacitance of 159 F g À1 . Further, it distributes an energy density of 49.87 Wh kg À1 at the power density of 845.45 W kg À1 with an excellent cyclic life of ~91.03% over 10 000 cycles.