空心炭球的制备及在双电层电容器中的应用进展

XU Kuang-liang; LIU Jing; YAN Zhao-xiong; JIN Mei; XU Zhi-hua

doi:10.1016/S1872-5805(20)60517-0

空心炭球的制备及在双电层电容器中的应用进展

doi: 10.1016/S1872-5805(20)60517-0

江汉大学光电化学材料与器件教育部重点实验室，湖北武汉 430056

基金项目: 国家自然科学基金（21871111）；湖北省杰出青年基金（2019CFA078）

详细信息

通讯作者:
晋　梅，博士，副教授. E-mail：hmay7321@126.com

徐志花，博士，教授. E-mail：xuzhihua78@sina.com

中图分类号: TQ127.1⁺1
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出版历程
- 收稿日期: 2019-10-14
- 修回日期: 2020-05-24
- 网络出版日期: 2021-03-16
- 刊出日期: 2021-07-30

Synthesis and use of hollow carbon spheres for electric double-layer capacitors

Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education, Jianghan University, Wuhan 430056, China

Funds: National Natural Science Foundation of China (21871111); Excellent Youth Foundation of Hubei Province of China (2019CFA078)

More Information

Author Bio:
徐匡亮，硕士. E-mail：XKL2229@163.com

Corresponding author: JIN Mei, Associate professor. E-mail: hmay7321@126.com; XU Zhi-hua, Professor. E-mail: xuzhihua78@sina.com

摘要

摘要: 超级电容器已逐渐成为一种重要的储能装置，依据储能机理可分为赝电容器和双电层电容器（Electric double-layer capacitors，EDLCs）。目前商用超级电容器主要是以炭材料为电极的EDLCs。空心炭球（Hollow carbon spheres，HCSs）具有大比表面积，良好的导电性，优异的电化学稳定性以及良好的机械强度等优点，其在EDLCs电极材料中的应用引起了研究者的广泛关注。本文对常用于HCSs合成的硬模板法、软模板法、无模板法和改进Stöber法以及HCSs在EDLCs中的电化学性能进行了综述，并对HCSs微结构中的比表面积、孔径尺寸和杂原子掺杂等因素与其电化学性能之间的关系进行了分析和归纳，以期为低成本、高活性HCSs应用在超级电容器和其他领域提供思路。
- 空心炭球 /
- 双电层电容器 /
- 结构 /
- 性能
Abstract: Supercapacitors have become an important energy storage device. Based on their energy storage mechanism, supercapacitors are generally categorized into pseudocapacitors and electric double-layer capacitors (EDLCs). Nowadays, carbon materials are used as the electrodes in commercial EDLCs. Hollow carbon spheres (HCSs) have attracted extensive attention for use as the electrode materials of EDLCs because of their large specific surface area, high electrical conductivity, excellent electrochemical stability and high mechanical strength. Progress on the preparation of HCSs is reviewed, including the hard and soft templating methods, template-free methods and the modified Stöber method. Their electrochemical performance as the electrode materials of EDLCs and the effect of their specific surface area, pore size and doped foreign atoms on their electrochemical performance are summarized, which gives insight into their low-cost preparation and high-performance for use in supercapacitors.
- Hollow carbon spheres /
- Electric double-layer capacitors /
- Microstructure /
- Performance

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FIG. 784. FIG. 784.

FIG. 784..

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Figure 1. The overall conception of this work related to the synthesis and electrochemical performance of HCSs in EDLCs^[24,29-33].

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Figure 2. (a) TEM image of amine-functionalized silica colloid and schematic illustration of the formation process of the carbon hollow-spheres, (b) TEM image of porous HCS, (c) plots of potential versus time at different current densities and (d) the variation of specific capacitance with 1000 charge-discharge cycles at the current density of 5 A g⁻¹ and the corresponding coulomb efficiency for the porous HCS electrodes^[54].

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Figure 3. (a) A schematic illustration depicting the synthesis route for N- and O-doped HCSs, (b) TEM image of HCSs-700, (c) GCD curves at the current density of 1 A g⁻¹ and (d) CV curves at the scan rate of 50 mV s⁻¹ of HCSs prepared at different carbonization temperatures^[30].

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Figure 4. (a) A schematic illustration of the synthesis of nitrogen-rich porous carbon spheres, (b) TEM image of NPC800, (c) CV curves at the scan rate of 5 mV s⁻¹ and (d) GCD curves at the current density of 0.5 A g⁻¹ of NPC prepared at different carbonization temperatures^[31,79].

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Figure 5. (a) A schematic illustration of the one-pot, surfactant-free synthesis of mesoporous carbon hollow spheres, (b) TEM image of MCHS, (c) GCD curves of MCHS and (d) cycling stability of MCHS at the current density of 10 A g⁻¹^[24].

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Figure 6. Normalized capacitance versus average pore size for different carbon materials in 1 mol L⁻¹ H₂SO₄ electrolyte^[111].

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Figure 7. Schematic of functional groups of N-doped HCSs^[47].

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Table 1. A comparison of electrochemical performance of HCSs prepared by different methods.

HCS sample	Synthetic method	Carbon precursor	Carbonization temperature (°C)	Specific surface area (m² g⁻¹)	Pore size (nm)	Current density (A g⁻¹)	Specific capacitance (F g⁻¹)	Electrolyte	Refs.
Surface-openings HCS	Hard templating	Resorcinol/ formaldehyde	800	670.0	4.18 and 12.55^a	0.1	272.2	1 M H₂SO₄	[15]
HCS	Hard templating	Resorcinol/ formaldehyde	800	555.6	3.87^a	0.1	210.7	1 M H₂SO₄	[15]
N-P-HCMs	Hard templating	Melamine/ formaldehyde	800	649	2.6 and 3.7^a	0.5	200	6 M KOH	[25]
N-HPCS	Hard templating	Dopamine	700	674.9	18 – 30	1	257	6 M KOH	[29]
HPCS	Hard templating	Furfuryl alcohol	900	2489	2 – 4	0.2	167	6 M KOH	[33]
HCSSg	Hard templating	Glucose	800	934	0.6 – 6	0.2	386	2 M KOH	[39]
HPCS	Hard templating	Furfuryl alcohol	800	669	1.2 – 3.0	1	240.0	6 M KOH	[40]
Activated HPCSs	Hard templating	Furfuryl alcohol	800	1290	1.5 – 3.0	1	303.9	6 M KOH	[40]
HCMSC	Hard templating	Phenol/ formaldehyde	900	1667	3.46^a	0.3	162	1 M Et₄NBF₄/AN	[44]
MHCS	Hard templating	C₂H₄	800	770	1.8 – 6.9	0.2	99	1 M H₂SO₄	[45]
N-PHCS	Hard templating	Polyaniline	600	213	4.5^b	0.5	213	6 M KOH	[47]
HMCSs	Hard templating	Polystyrene	600	1321	4.6^a	0.5	157	6 M KOH	[48]
HMCSs	Hard templating	Carbonaceous gas	800	1189	2.7^a	0.2	180	6 M KOH	[49]
Activated HCSs	Hard templating	Polypyrrole	900	923	0.55 – 15	0.2	535	6 M KOH	[51]
N-PCS	Hard templating	Polyacrylamide	650	648	0.5 – 10	0.5	194.7	6 M KOH	[52]
N-HCS	Hard templating	Resorcinol and hexamethylenetetramine	600	405	1 – 4.5	0.5	120	6 M KOH	[53]
CHSs	Hard templating	Glucose	800	658	40^a	0.5	270	6 M KOH	[54]
HCSs	Soft templating	Poly(o-phenylenediamine)	600	145	3.06^b	-	-	6 M KOH	[30]
HCSs	Soft templating	Poly(o-phenylenediamine)	700	355	3.83^b	0.5	210	6 M KOH	[30]
HCSs	Soft templating	Poly(o-phenylenediamine)	800	212	1.19^b	-	-	6 M KOH	[30]
HCSs	Soft templating	Poly(styrene-co-divinylbenzene)	700	805	0.7^a	0.5	561	2 M KOH	[57]
PCS	Soft templating	Glucose	800	1610	3.5^b	0.5	80	1 M TEA-BF₄/AN	[70]
PCS	Soft templating	Glucose	800	1610	3.5^b	0.5	219	6 M KOH	[70]
N-PCS	Template-free	Porous organic frameworks	800	525	40^a	0.5	230	5 M KOH	[31]
HCS	Template-free	Corn starch	800	517.46	2 – 10	1	265.4	6 M KOH	[32]
N-HCS	Template-free	Resorcinol/formaldehyde	800	946	–	1	196	6 M KOH	[73]
HCS	Template-free	Sucrose	1100	1106	2^a	0.1	112	6 M KOH	[76]
N-HCS	Template-free	3-aminophenol/ formaldehyde	800	911	2.7^a	1	194	6 M KOH	[128]
MCHS	Modified Stöber method	Resorcinol/ formaldehyde	700	1582	7.5^a	1	310.4	6 M KOH	[24]
N-HMCSs	Modified Stöber method	Resorcinol/ formaldehyde	600	1158	5.0^b	1	159	6 M KOH	[90]
Yolk–shell CS	Modified Stöber method	Resorcinol/ formaldehyde	800	616	5.7^a	0.5	330	6 M KOH	[91]
N-HCS	Modified Stöber method	Polystyrene/ polyaniline	800	953.8	4.1^a	0.5	436.5	6 M KOH	[92]
HMCSs	Modified Stöber method	Resorcinol/ formaldehyde	800	1425	2.1^a	0.5	352	6 M KOH	[93]
N-HMCSs	Modified Stöber method	Resorcinol/ formaldehyde	800	2001	2.4^a	1	300	1 M H₂SO₄	[105]
N-HMCSs	Modified Stöber method	3-aminophenol/ formaldehyde	600	1006	3^a	1	170	6 M KOH	[129]
Note：^a pore width at the maximum of the pore size distribution；^b average pore size; M: mα L⁻¹.

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