Oxygen-enriched activated carbons from pomelo peel in high energy density supercapacitors

A novel redox-mediated gel polymer (PVA–H2SO4–ARS) is prepared, and a symmetric supercapacitor using the gel polymer as electrolyte and activated carbon as electrode is also assembled.

Download Full-text

Nitrogen-Doped Hierarchical Porous Activated Carbon Derived from Paddy for High-Performance Supercapacitors

Materials ◽

10.3390/ma14020318 ◽

2021 ◽

Vol 14 (2) ◽

pp. 318

Author(s):

Yudan Yuan ◽

Yi Sun ◽

Zhichen Feng ◽

Xingjian Li ◽

Ruowei Yi ◽

...

Keyword(s):

Activated Carbon ◽

Energy Density ◽

Specific Capacitance ◽

High Performance ◽

High Energy ◽

High Energy Density ◽

Scale Production ◽

Nitrogen Doped ◽

Hierarchical Porous ◽

Porous Activated Carbon

A facile and environmentally friendly fabrication is proposed to prepare nitrogen-doped hierarchical porous activated carbon via normal-pressure popping, one-pot activation and nitrogen-doping process. The method adopts paddy as carbon precursor, KHCO3 and dicyandiamide as the safe activating agent and nitrogen dopant. The as-prepared activated carbon presents a large specific surface area of 3025 m2·g−1 resulting from the synergistic effect of KHCO3 and dicyandiamide. As an electrode material, it shows a maximum specific capacitance of 417 F·g−1 at a current density of 1 A·g−1 and very good rate performance. Furthermore, the assembled symmetric supercapacitor presents a large specific capacitance of 314.6 F·g−1 and a high energy density of 15.7 Wh·Kg−1 at 1 A·g−1, maintaining 14.4 Wh·Kg−1 even at 20 A·g−1 with the energy density retention of 91.7%. This research demonstrates that nitrogen-doped hierarchical porous activated carbon derived from paddy has a significant potential for developing a high-performance renewable supercapacitor and provides a new route for economical and large-scale production in supercapacitor application.

Download Full-text

Correction: Oxygen-enriched activated carbons from pomelo peel in high energy density supercapacitors

RSC Advances ◽

10.1039/c4ra90041c ◽

2014 ◽

Vol 4 (105) ◽

pp. 61045-61045

Author(s):

Chao Peng ◽

Junwei Lang ◽

Shan Xu ◽

Xiaolai Wang

Keyword(s):

Energy Density ◽

Activated Carbons ◽

High Energy ◽

High Energy Density ◽

Pomelo Peel

Download Full-text

1.8 V Aqueous Symmetric Carbon-Based Supercapacitors with Agarose-Bound Activated Carbons in an Acidic Electrolyte

Nanomaterials ◽

10.3390/nano11071731 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1731

Author(s):

Chih-Chung Lai ◽

Feng-Hao Hsu ◽

Su-Yang Hsu ◽

Ming-Jay Deng ◽

Kueih-Tzu Lu ◽

...

Keyword(s):

Activated Carbon ◽

Sulfuric Acid ◽

Energy Density ◽

Activated Carbons ◽

High Energy ◽

Aqueous Electrolytes ◽

Alternative Material ◽

Aqueous Cells ◽

Acidic Electrolyte ◽

Cycling Behavior

The specific energy of an aqueous carbon supercapacitor is generally small, resulting mainly from a narrow potential window of aqueous electrolytes. Here, we introduced agarose, an ecologically compatible polymer, as a novel binder to fabricate an activated carbon supercapacitor, enabling a wider potential window attributed to a high overpotential of the hydrogen-evolution reaction (HER) of agarose-bound activated carbons in sulfuric acid. Assembled symmetric aqueous cells can be galvanostatically cycled up to 1.8 V, attaining an enhanced energy density of 13.5 W h/kg (9.5 µW h/cm2) at 450 W/kg (315 µW/cm2). Furthermore, a great cycling behavior was obtained, with a 94.2% retention of capacitance after 10,000 cycles at 2 A/g. This work might guide the design of an alternative material for high-energy aqueous supercapacitors.

Download Full-text

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

Materials ◽

10.3390/ma14010122 ◽

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.

Download Full-text