Highly active N, O-doped hierarchical porous carbons for high-energy supercapacitors

Zhou, Ziyang; Liu, Miao; Duan, Hui; Wang, Zhiwei; Lv, Yaokang; Xiong, Wei; Zhu, Duanwei; Li, Liangchun; Liu, Mingxian; Gan, Lihua

doi:10.1016/j.cclet.2020.02.026

Cited by 89 publications

(24 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[ 18,19 ] However, since the small‐sized micropores ( d <0.5 nm) are ion‐inaccessible, as well as the charge storage efficiency of small‐sized mesopores ( d <4 nm) is comparable to that of micropores, the specific capacity of carbon‐based material is not always linearly related to the micropore volume. [ 2,20–22 ] Therefore, the active site contributors should be defined as ion‐accessible micropores and small‐sized mesopores. In view of this, the ideal carbon‐based materials for SCs should be a hierarchical porous carbon (HPC), in which the ion‐accessible micropores and small‐sized mesopores are dominated and supplemented by a reasonable proportion of supermesopores ( d >4 nm).…”

Section: Introductionmentioning

confidence: 99%

Cucurbit[6]uril‐Derived Sub‐4 nm Pores‐Dominated Hierarchical Porous Carbon for Supercapacitors: Operating Voltage Expansion and Pore Size Matching

Qiu

Kang

Wei

et al. 2020

Small

View full text Add to dashboard Cite

However, the inferior energy density of SCs (typically < 5 Wh kg −1) severely restricts their widespread application in large-scale energy storage. [3-5] Based on the evaluation criterion of energy density, the energy density of SCs is proportional to the specific capacity and the square of the operating voltage of the device. [3,6] Therefore, in principle, the key to construct high energy density SCs lies in the electrode material with superb intrinsic characteristics and the electrolyte with high voltage window that is highly matched with the electrode material. To date, many kinds of active materials, such as transition metal hydroxides/oxides, phosphates, and carbon-based materials have been developed as electrode materials for SCs. [7-12] Among them, compounds based on the Faraday reaction tend to possess superior theoretical specific capacity, but due to poor intrinsic conductivity, sluggish kinetics, and collapse-prone structure, the key parameters such as rate capability and cyclability are unsatisfactory. [2,13] As a versatile SCs electrode material, carbon-based materials based on reversible ion adsorption/desorption not only integrate high specific capacity, excellent rate capability, and outstanding cycling performance, but also compatible with various electrolyte systems such as aqueous, organic, and ionic liquid. [14,15] In view of energy storage characteristics, pore structure plays the most vital role in electrochemical properties of carbon-based materials. [16,17] In the inherent cognition, micropores provide active sites to store charge, mesopores contribute channels to promote ion diffusion and transfer, and macropores act as ion buffers. [18,19] However, since the small-sized micropores (d <0.5 nm) are ioninaccessible, as well as the charge storage efficiency of smallsized mesopores (d <4 nm) is comparable to that of micropores, the specific capacity of carbon-based material is not always linearly related to the micropore volume. [2,20-22] Therefore, the active site contributors should be defined as ion-accessible micropores and small-sized mesopores. In view of this, the ideal carbonbased materials for SCs should be a hierarchical porous carbon (HPC), in which the ion-accessible micropores and small-sized mesopores are dominated and supplemented by a reasonable proportion of supermesopores (d >4 nm). The intrinsic properties of carbon-based material and the voltage window of electrolyte are the two key barriers to restrict the energy density of carbonbased supercapacitors (SCs). Herein, a cucurbit[6]uril-derived nitrogen-doped hierarchical porous carbon (CBCx) with unique pore structure characteristics is synthesized and successfully applied to construct SCs based on different electrolyte systems. Owing to narrow pore size distribution (0.5-4 nm), colossal ion-accessible pore volume, prominent supermesopore volume, and reasonable heteroatom configuration, the CBCx-based SCs demonstrate excellent electrochemical performances with high operating voltages in two distinct systems. The optimal SCs...

show abstract

Section: Introductionmentioning

confidence: 99%

Cucurbit[6]uril‐Derived Sub‐4 nm Pores‐Dominated Hierarchical Porous Carbon for Supercapacitors: Operating Voltage Expansion and Pore Size Matching

Qiu

Kang

Wei

et al. 2020

Small

View full text Add to dashboard Cite

show abstract

“…At this point, it is important to note that electrodes with a high content of functional groups can also contribute to the energy density of cells through the presence of reversible redox reactions (pseudocapacitance). 7,[33][34] This mechanism is faradic in nature and results in the presence of plateaus in the galvanostatic curves at specific potentials, promoting great distortions in the triangular profile of a supercapacitor. 5,35 It is well known that pseudocapacitance is more common and relevant in aqueous media, when acid or basic electrolytes are used.…”

Section: Resultsmentioning

confidence: 99%

Insights on the Behavior of Imidazolium Ionic Liquids as Electrolytes in Carbon-Based Supercapacitors: An Applied Electrochemical Approach

et al. 2020

View full text Add to dashboard Cite

This study aims to increase the knowledge on the interactions that occur at the electrode/electrolyte interface in carbon-based electric double layer capacitors (EDLC) when solventfree ionic liquids are used as electrolytes. Many previous studies found in the literature are conducted using theoretical approaches and they are unable to model all the variables and the complexity of an actual device with a complex carbon surface and an ionic liquid (IL). Here, the compatibility between imidazolium ionic liquids and different carbon materialsan activated carbon (AC), a mesoporous carbon (MES), multi-walled carbon nanotubes (MWCNT), and reduced graphene oxide (RGO) -is empirically investigated applying synchronous chronopotentiometric tests to various symmetrical EDLCs. The study of the simultaneous evolution of the cell and electrode potentials of the various carbon/ILs cells, monitoring the evolution of specific capacitances and electrical resistances for each independent electrode, allows inferring about the ion-electrode compatibility, the limiting factors for charge accumulation and its impacts on the performance of the global cell. The results indicate that the sp 2 structures of MWCNT and RGO favor interactions with the EMI + cation on the negative electrode.In the positive electrodes, MES and AC favor interactions with the BF4and TFSIanions, respectively, yielding a higher specific capacitance and lower resistance.

show abstract

“…1a) in CC-CO 3 O 4 is confirmed by steep uptake of nitrogen (P/P 0 o 0.05), manifesting copious micropores. 35,36 The average pore diameters Dads and Ddes (Dads and Ddes are the average pore diameters for BJH adsorption and desorption) were found to be 4.94 and 4.77 nm respectively. Surface area of the CC-CO 220), (311), (400), ( 422), (511), (440), and (533) planes of cubic structure (PDF card: 42-1467), respectively.…”

Section: Surface Xrd Raman Morphology and Chemical Compositional mentioning

confidence: 99%

Carbon coated cobalt oxide (CC-CO₃O₄) as electrode material for supercapacitor applications

2021

View full text Add to dashboard Cite

show abstract

Highly active N, O-doped hierarchical porous carbons for high-energy supercapacitors

Cited by 89 publications

References 52 publications

Cucurbit[6]uril‐Derived Sub‐4 nm Pores‐Dominated Hierarchical Porous Carbon for Supercapacitors: Operating Voltage Expansion and Pore Size Matching

Cucurbit[6]uril‐Derived Sub‐4 nm Pores‐Dominated Hierarchical Porous Carbon for Supercapacitors: Operating Voltage Expansion and Pore Size Matching

Insights on the Behavior of Imidazolium Ionic Liquids as Electrolytes in Carbon-Based Supercapacitors: An Applied Electrochemical Approach

Carbon coated cobalt oxide (CC-CO₃O₄) as electrode material for supercapacitor applications

Contact Info

Product

Resources

About

Highly active N, O-doped hierarchical porous carbons for high-energy supercapacitors

Cited by 89 publications

References 52 publications

Cucurbit[6]uril‐Derived Sub‐4 nm Pores‐Dominated Hierarchical Porous Carbon for Supercapacitors: Operating Voltage Expansion and Pore Size Matching

Cucurbit[6]uril‐Derived Sub‐4 nm Pores‐Dominated Hierarchical Porous Carbon for Supercapacitors: Operating Voltage Expansion and Pore Size Matching

Insights on the Behavior of Imidazolium Ionic Liquids as Electrolytes in Carbon-Based Supercapacitors: An Applied Electrochemical Approach

Carbon coated cobalt oxide (CC-CO3O4) as electrode material for supercapacitor applications

Contact Info

Product

Resources

About

Carbon coated cobalt oxide (CC-CO₃O₄) as electrode material for supercapacitor applications