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Thermochemically activated carbon as an electrode material for supercapacitors.

Ostafiychuk BK, Budzulyak IM, Rachiy BI, Vashchynsky VM, Mandzyuk VI, Lisovsky RP, Shyyko LO - Nanoscale Res Lett (2015)

Bottom Line: The results of electrochemical studies of nanoporous carbon as electrode material for electrochemical capacitors (EC) are presented in this work.It is established that there is an optimal ratio of 1:1 between content of KOH and carbon material at chemical activation, while the maximum specific capacity of NCM is 180 F/g.An equivalent electrical circuit, which allows modeling of the impedance spectra in the frequency range of 10(-2) to 10(5) Hz, is proposed, and a physical interpretation of each element of the electrical circuit is presented.

View Article: PubMed Central - PubMed

Affiliation: Vasyl Stefanyk PreCarpathian National University, 57 Shevchenko Str., Ivano-Frankivsk, 76018 Ukraine.

ABSTRACT
The results of electrochemical studies of nanoporous carbon as electrode material for electrochemical capacitors (EC) are presented in this work. Nanoporous carbon material (NCM) was obtained from the raw materials of plant origin by carbonization and subsequent activation in potassium hydroxide. It is established that there is an optimal ratio of 1:1 between content of KOH and carbon material at chemical activation, while the maximum specific capacity of NCM is 180 F/g. An equivalent electrical circuit, which allows modeling of the impedance spectra in the frequency range of 10(-2) to 10(5) Hz, is proposed, and a physical interpretation of each element of the electrical circuit is presented.

No MeSH data available.


The charge-discharge curves of the EC based on the NCM. C31 —□—, C32 —Δ —, C33 —○—, C34 —◊—. (Discharge current is 20 mA).
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Fig7: The charge-discharge curves of the EC based on the NCM. C31 —□—, C32 —Δ —, C33 —○—, C34 —◊—. (Discharge current is 20 mA).

Mentions: One of the important parameters of EC is Coulomb efficiency, which indicates the ratio of the discharge capacity to charge capacity during cycling. In order to determine this parameter, we took the charge/discharge curves of EC after 1,000 cycles (Figure 7). The Coulomb efficiency after several cycles stabilized at the level of 97% to 99% and practically did not change during the study. It shows that the studied material provides stability behavior and durability of capacitors. The capacity change during cycling is less than 2%.Figure 7


Thermochemically activated carbon as an electrode material for supercapacitors.

Ostafiychuk BK, Budzulyak IM, Rachiy BI, Vashchynsky VM, Mandzyuk VI, Lisovsky RP, Shyyko LO - Nanoscale Res Lett (2015)

The charge-discharge curves of the EC based on the NCM. C31 —□—, C32 —Δ —, C33 —○—, C34 —◊—. (Discharge current is 20 mA).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4385132&req=5

Fig7: The charge-discharge curves of the EC based on the NCM. C31 —□—, C32 —Δ —, C33 —○—, C34 —◊—. (Discharge current is 20 mA).
Mentions: One of the important parameters of EC is Coulomb efficiency, which indicates the ratio of the discharge capacity to charge capacity during cycling. In order to determine this parameter, we took the charge/discharge curves of EC after 1,000 cycles (Figure 7). The Coulomb efficiency after several cycles stabilized at the level of 97% to 99% and practically did not change during the study. It shows that the studied material provides stability behavior and durability of capacitors. The capacity change during cycling is less than 2%.Figure 7

Bottom Line: The results of electrochemical studies of nanoporous carbon as electrode material for electrochemical capacitors (EC) are presented in this work.It is established that there is an optimal ratio of 1:1 between content of KOH and carbon material at chemical activation, while the maximum specific capacity of NCM is 180 F/g.An equivalent electrical circuit, which allows modeling of the impedance spectra in the frequency range of 10(-2) to 10(5) Hz, is proposed, and a physical interpretation of each element of the electrical circuit is presented.

View Article: PubMed Central - PubMed

Affiliation: Vasyl Stefanyk PreCarpathian National University, 57 Shevchenko Str., Ivano-Frankivsk, 76018 Ukraine.

ABSTRACT
The results of electrochemical studies of nanoporous carbon as electrode material for electrochemical capacitors (EC) are presented in this work. Nanoporous carbon material (NCM) was obtained from the raw materials of plant origin by carbonization and subsequent activation in potassium hydroxide. It is established that there is an optimal ratio of 1:1 between content of KOH and carbon material at chemical activation, while the maximum specific capacity of NCM is 180 F/g. An equivalent electrical circuit, which allows modeling of the impedance spectra in the frequency range of 10(-2) to 10(5) Hz, is proposed, and a physical interpretation of each element of the electrical circuit is presented.

No MeSH data available.