scholarly journals Electrochemical properties of kenaf-based activated carbon monolith for supercapacitor electrode applications

RSC Advances ◽  
2021 ◽  
Vol 11 (61) ◽  
pp. 38515-38522
Author(s):  
Han Yul Park ◽  
Minhu Huang ◽  
Tae-Ho Yoon ◽  
Kyung Hun Song
Keyword(s):  
Activated Carbon ◽  
Energy Density ◽  
Electrochemical Properties ◽  
Specific Capacitance ◽  
Power Density ◽  
Supercapacitor Electrode ◽  
Cycling Test ◽  
Carbon Monolith ◽  
Activated Carbon Monolith

Monolithic carbon from kenaf-based fiber for supercapacitor electrode application provided a specific capacitance of 212 F g−1via GCD at 1 A g−1, converting to an energy density of 6 W h kg−1 at the power density of 215 W kg−1 as well as 95.9% retention upon 5000 cycling test.

scholarly journals In Situ Fabrication of Activated Carbon from a Bio-Waste Desmostachya bipinnata for the Improved Supercapacitor Performance

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Gopal Krishna Gupta ◽  
Pinky Sagar ◽  
Sumit Kumar Pandey ◽  
Monika Srivastava ◽  
A. K. Singh ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Energy Density ◽  
Power Density ◽  
Supercapacitor Electrode ◽  
In Situ Fabrication ◽  
Transmission Electron ◽  
Good Energy ◽  
Supercapacitor Performance ◽  
Operating Potential

AbstractHerein, we demonstrate the fabrication of highly capacitive activated carbon (AC) using a bio-waste Kusha grass (Desmostachya bipinnata), by employing a chemical process followed by activation through KOH. The as-synthesized few-layered activated carbon has been confirmed through X-ray powder diffraction, transmission electron microscopy, and Raman spectroscopy techniques. The chemical environment of the as-prepared sample has been accessed through FTIR and UV–visible spectroscopy. The surface area and porosity of the as-synthesized material have been accessed through the Brunauer–Emmett–Teller method. All the electrochemical measurements have been performed through cyclic voltammetry and galvanometric charging/discharging (GCD) method, but primarily, we focus on GCD due to the accuracy of the technique. Moreover, the as-synthesized AC material shows a maximum specific capacitance as 218 F g−1 in the potential window ranging from − 0.35 to + 0.45 V. Also, the AC exhibits an excellent energy density of ~ 19.3 Wh kg−1 and power density of ~ 277.92 W kg−1, respectively, in the same operating potential window. It has also shown very good capacitance retention capability even after 5000th cycles. The fabricated supercapacitor shows a good energy density and power density, respectively, and good retention in capacitance at remarkably higher charging/discharging rates with excellent cycling stability. Henceforth, bio-waste Kusha grass-derived activated carbon (DP-AC) shows good promise and can be applied in supercapacitor applications due to its outstanding electrochemical properties. Herein, we envision that our results illustrate a simple and innovative approach to synthesize a bio-waste Kusha grass-derived activated carbon (DP-AC) as an emerging supercapacitor electrode material and widen its practical application in electrochemical energy storage fields.

Mesoporous hollow carbons on graphene and their electrochemical properties

RSC Advances ◽  
2015 ◽  
Vol 5 (89) ◽  
pp. 73119-73125 ◽  
Author(s):  
G. H. Jeong ◽  
I. Lee ◽  
J.-G. Kang ◽  
H. Lee ◽  
S. Yoon ◽  
...  
Keyword(s):  
Energy Density ◽  
Electrochemical Properties ◽  
Power Density ◽  
Supercapacitor Electrode ◽  
Graphene Surface ◽  
Hollow Carbon

We synthesized mesoporous hollow carbon on a graphene surface (MHCG). When applied into supercapacitor electrode, MHCG electrode exhibited outstanding maintenance of energy density above 30 W h kg−1 even under 1 kW kg−1 power density.

scholarly journals Achieving Ultrahigh Cycling Stability and Extended Potential Window for Supercapacitors through Asymmetric Combination of Conductive Polymer Nanocomposite and Activated Carbon

Polymers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1678 ◽  
Author(s):  
Gul ◽  
Shah ◽  
Bilal
Keyword(s):  
Graphene Oxide ◽  
Activated Carbon ◽  
Charge Transfer ◽  
Energy Density ◽  
Specific Capacitance ◽  
Power Density ◽  
Current Density ◽  
Coulombic Efficiency ◽  
Cycling Stability ◽  
Transfer Resistance

Conducting polymers and carbon-based materials such as graphene oxide (GO) and activated carbon (AC) are the most promising capacitive materials, though both offer charge storage through different mechanisms. However, their combination can lead to some unusual results, offering improvement in certain properties in comparison with the individual materials. Cycling stability of supercapacitors devices is often a matter of concern, and extensive research is underway to improve this phenomena of supercapacitive devices. Herein, a high-performance asymmetric supercapacitor device was fabricated using graphene oxide–polyaniline (GO@PANI) nanocomposite as positive electrode and activated carbon (AC) as negative electrode. The device showed 142 F g-1 specific capacitance at 1 A g-1 current density with capacitance retention of 73.94% at higher current density (10 A g-1). Most importantly, the device exhibited very high electrochemical cycling stability. It retained 118.6% specific capacitance of the starting value after 10,000 cycles at 3 Ag-1 and with coulombic efficiency of 98.06 %, indicating great potential for practical applications. Very small solution resistance (Rs, 0.640 Ω) and charge transfer resistance (Rct, 0.200 Ω) were observed hinting efficient charge transfer and fast ion diffusion. Due to asymmetric combination, potential window was extended to 1.2 V in aqueous electrolyte, as a result higher energy density (28.5 Wh kg-1) and power density of 2503 W kg-1 were achieved at the current density 1 Ag-1. It also showed an aerial capacitance of 57 mF cm-2 at current 3.2 mA cm-2. At this current density, its energy density was maximum (0.92 mWh cm-2) with power density (10.47 W cm-2).

scholarly journals Electrochemical properties of an activated carbon xerogel monolith from resorcinol–formaldehyde for supercapacitor electrode applications

RSC Advances ◽  
2021 ◽  
Vol 11 (53) ◽  
pp. 33192-33201
Author(s):  
Minhu Huang ◽  
Seung Joon Yoo ◽  
Jae-Suk Lee ◽  
Tae-Ho Yoon
Keyword(s):  
Activated Carbon ◽  
Electrochemical Properties ◽  
Specific Capacitance ◽  
Carbon Xerogel ◽  
Supercapacitor Electrode ◽  
Resorcinol Formaldehyde

A monolithic carbon xerogel electrode for supercapacitors was prepared from resorcinol–formaldehyde, providing a specific capacitance of 323 F g−1via GCD at 1 A g−1 and 100% retention upon 5000 cycling tests.

scholarly journals Na0.76V6O15/Activated Carbon Hybrid Cathode for High-Performance Lithium-Ion Capacitors

Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 122
Author(s):  
Renwei Lu ◽  
Xiaolong Ren ◽  
Chong Wang ◽  
Changzhen Zhan ◽  
Ding Nan ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Energy Density ◽  
Power Density ◽  
Cathode Materials ◽  
Low Cost ◽  
Lithium Ion ◽  
High Energy ◽  
Cycling Stability ◽  
High Energy Density ◽  
Artificial Graphite

Lithium-ion hybrid capacitors (LICs) are regarded as one of the most promising next generation energy storage devices. Commercial activated carbon materials with low cost and excellent cycling stability are widely used as cathode materials for LICs, however, their low energy density remains a significant challenge for the practical applications of LICs. Herein, Na0.76V6O15 nanobelts (NaVO) were prepared and combined with commercial activated carbon YP50D to form hybrid cathode materials. Credit to the synergism of its capacitive effect and diffusion-controlled faradaic effect, NaVO/C hybrid cathode displays both superior cyclability and enhanced capacity. LICs were assembled with the as-prepared NaVO/C hybrid cathode and artificial graphite anode which was pre-lithiated. Furthermore, 10-NaVO/C//AG LIC delivers a high energy density of 118.9 Wh kg−1 at a power density of 220.6 W kg−1 and retains 43.7 Wh kg−1 even at a high power density of 21,793.0 W kg−1. The LIC can also maintain long-term cycling stability with capacitance retention of approximately 70% after 5000 cycles at 1 A g−1. Accordingly, hybrid cathodes composed of commercial activated carbon and a small amount of high energy battery-type materials are expected to be a candidate for low-cost advanced LICs with both high energy density and power density.

scholarly journals Electrochemical Performance of Aluminum Doped Ni1−xAlxCo2O4 Hierarchical Nanostructure: Experimental and Theoretical Study

Processes ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 1750
Author(s):  
Deepa Guragain ◽  
Romakanta Bhattarai ◽  
Jonghyun Choi ◽  
Wang Lin ◽  
Ram Krishna Gupta ◽  
...  
Keyword(s):  
Energy Density ◽  
Electrochemical Performance ◽  
Band Gap ◽  
Specific Capacitance ◽  
Surface Area ◽  
Power Density ◽  
High Power ◽  
Energy Band ◽  
High Specific Capacitance ◽  
High Power Density

For electrochemical supercapacitors, nickel cobaltite (NiCo2O4) has emerged as a new energy storage material. The electrocapacitive performance of metal oxides is significantly influenced by their morphology and electrical characteristics. The synthesis route can modulate the morphological structure, while their energy band gaps and defects can vary the electrical properties. In addition to modifying the energy band gap, doping can improve crystal stability and refine grain size, providing much-needed surface area for high specific capacitance. This study evaluates the electrochemical performance of aluminum-doped Ni1−xAlxCo2O4 (0 ≤ x ≤ 0.8) compounds. The Ni1−xAlxCo2O4 samples were synthesized through a hydrothermal method by varying the Al to Ni molar ratio. The physical, morphological, and electrochemical properties of Ni1−xAlxCo2O4 are observed to vary with Al3+ content. A morphological change from urchin-like spheres to nanoplate-like structures with a concomitant increase in the surface area, reaching up to 189 m2/g for x = 0.8, was observed with increasing Al3+ content in Ni1−xAlxCo2O4. The electrochemical performance of Ni1−xAlxCo2O4 as an electrode was assessed in a 3M KOH solution. The high specific capacitance of 512 F/g at a 2 mV/s scan rate, 268 F/g at a current density of 0.5 A/g, and energy density of 12.4 Wh/kg was observed for the x = 0.0 sample, which was reduced upon further Al3+ substitution. The as-synthesized Ni1−xAlxCo2O4 electrode exhibited a maximum energy density of 12.4 W h kg−1 with an outstanding high-power density of approximately 6316.6 W h kg−1 for x = 0.0 and an energy density of 8.7 W h kg−1 with an outstanding high-power density of approximately 6670.9 W h kg−1 for x = 0.6. The capacitance retention of 97% and 108.52% and the Coulombic efficiency of 100% and 99.24% were observed for x = 0.0 and x = 0.8, respectively. First-principles density functional theory (DFT) calculations show that the band-gap energy of Ni1−xAlxCo2O4 remained largely invariant with the Al3+ substitution for low Al3+ content. Although the capacitance performance is reduced upon Al3+ doping, overall, the Al3+ doped Ni1−xAlxCo2O4 displayed good energy, powder density, and retention performance. Thus, Al3+ could be a cost-effective alternative in replacing Ni with the performance trade off.

Sign in / Sign up

Export Citation Format

Share Document