High-Rate Electrochemical Capacitors Based on Ordered Mesoporous Silicon Carbide-Derived Carbon

Korenblit, Yair; Rose, Marcus; Kockrick, Emanuel; Borchardt, Lars; Kvit, A.; Kaskel, Stefan; Yushin, Gleb

doi:10.1021/nn901825y

Cited by 460 publications

(333 citation statements)

References 46 publications

Supporting

Mentioning

310

Contrasting

Unclassified

Order By: Relevance

“…As a result, the voltage shows a larger variation with charge, and the capacitance decreases. Our findings also help to explain the excellent high-current performances of hierarchical meso/micropore structures 41 and zeolitetemplated carbons with pore connectivity in three dimensions. 44 9…”

mentioning

confidence: 55%

“…21 Kondrat et al have suggested that ideally the carbon pores would be initially empty of ions (ionophobic pores) to facilitate fast charging, 16,24,40 Our measurements on carbons with different pore sizes help to explain previous electrochemical studies of charging dynamics. 1,[41][42][43] For carbons with smaller average pore sizes and fewer mesopores (< 2 nm), the capacitance decreased more rapidly as the current density was increased.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Direct observation of ion dynamics in supercapacitor electrodes using in situ diffusion NMR spectroscopy

et al. 2017

View full text Add to dashboard Cite

Ionic transport inside porous carbon electrodes underpins the storage of energy in supercapacitors and the rate at which they can charge and discharge, yet few studies have elucidated the materials properties that influence ion dynamics. Here we use in situ pulsed field gradient NMR spectroscopy to measure ionic diffusion in supercapacitors directly. We find that confinement in the nanoporous electrode structures decreases the effective self-diffusion coefficients of ions by over two orders of magnitude compared to neat electrolyte, and in-pore diffusion is modulated by changes in ion populations at the electrode-electrolyte interface during charging.Electrolyte concentration and carbon pore size distributions also affect in-pore diffusion and the movement of ions in and out of the nanopores. In light of our findings we propose that controlling the charging mechanism may allow the tuning of the energy and power performances of supercapacitors for a range of different applications.As renewable energy and green technologies such as electric vehicles become prevalent, we must develop new ways to store and release energy on a range of timescales. Rechargeable batteries are ideal for timescales of minutes or hours (electric cars, portable electronic devices, grid storage etc.), while supercapacitors are more promising for second or sub-second timescales and are increasingly being used for transport applications where rapid charging and discharging are required. The superior power handling and cycle lifetime of supercapacitors comes at the expense of energy density, with recent materials-driven research aiming to address this issue by fine-tuning the nanoporous structure of the carbon electrodes, 1,2 and by using ionic liquid electrolytes that are stable at higher voltages. 3,4 Both approaches have afforded some increases in energy density, though not without sacrificing power density. The delicate balance between energy and power density must be understood if supercapacitors are to be used in a wide range of applications.Fundamental studies based on spectroscopic, 5-14 and theoretical, 15-18 methods have recently revealed the complex nature of charging in supercapacitors. Prior to charging, the electrode pores contain a large number of electrolyte ions, 15,19,20 and as a result charge storage is generally more complex than simple counter-ion adsorption (counter-ions are defined as having charge opposite to the electrode in which they are located). [5][6][7]15 A range of different charging mechanisms can operate

show abstract

mentioning

confidence: 55%

mentioning

confidence: 99%

Direct observation of ion dynamics in supercapacitor electrodes using in situ diffusion NMR spectroscopy

et al. 2017

View full text Add to dashboard Cite

show abstract

“…This behavior is in accordance with its low electronic conductivity and resistance to ion transport within the porous structure as was confirmed in the EIS measurements (see Figure 4c). The rate capability of the activated microspheres compares well with that of advanced porous carbons, including hierarchical porous carbons [55][56][57][58]. The stability of these materials in organic electrolyte was evaluated by charge-discharge and N-CSA-700 at their maximum working voltage window in volumetric units.…”

Section: Electrochemical Characterizationmentioning

confidence: 99%

N-doped microporous carbon microspheres for high volumetric performance supercapacitors

Ferrero

Fuertes

Sevilla

2015

Electrochimica Acta

View full text Add to dashboard Cite

N-doped highly dense uniform carbon microspheres of around 1 µm have been prepared by a nanocasting strategy using silica particles as template and a nitrogen-rich substance (i.e. pyrrole) as carbon precursor. These carbon microspheres possess a large number of nitrogen functional groups (~ 9 wt % N), a high BET surface area of up to ~ 1300 m 2 g -1 with a porosity made up mostly of micropores (< 2 nm), and a high packing density of 0.97 g cm -3 . They also show a remarkable volumetric capacitance of ca. 290 F cm -3 in H 2 SO 4 as a result of pseudocapacitance effects arising from the N-groups, such that they are able to keep 50 % of the capacitance at a high current density of 40 A g -1 .An additional chemical activation process with KOH has been performed to enhance the microporous network. These highly porous microspheres (2690 m 2 g -1 ), that have a lower nitrogen content (~ 2 % wt), can achieve 92 F cm -3 in TEABF 4 /AN while displaying 83 % of capacitance retention at a high current density of 40 A g -1 .

show abstract

“…The interaction between PPy and CDC in the composite was investigated using Raman spectrometry. It is known from literature that typical disordered carbons as CDC hold disorder-induced D-band associated with a double-resonance Raman process located at 1340 cm -1 [29,30]. The position of this band may vary, depending on the structure of the disordered carbon and the presence of impurities or functional groups.…”

Section: Synthesismentioning

confidence: 99%

Novel actuators based on polypyrrole/carbide-derived carbon hybrid materials

Torop

Aabloo

Jager

2014

Carbon

View full text Add to dashboard Cite

High-Rate Electrochemical Capacitors Based on Ordered Mesoporous Silicon Carbide-Derived Carbon

Cited by 460 publications

References 46 publications

Direct observation of ion dynamics in supercapacitor electrodes using in situ diffusion NMR spectroscopy

Direct observation of ion dynamics in supercapacitor electrodes using in situ diffusion NMR spectroscopy

N-doped microporous carbon microspheres for high volumetric performance supercapacitors

Novel actuators based on polypyrrole/carbide-derived carbon hybrid materials

Contact Info

Product

Resources

About