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1.
Three‐Dimensional Nitrogen‐Doped Hierarchical Porous Carbon as an Electrode for High‐Performance Supercapacitors
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Jing Tang Dr. Tao Wang Dr. Rahul R. Salunkhe Prof. Saad M. Alshehri Dr. Victor Malgras Prof. Yusuke Yamauchi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(48):17293-17298
A facile and sustainable procedure for the synthesis of nitrogen‐doped hierarchical porous carbons with a three‐dimensional interconnected framework (NHPC‐3D) was developed. The strategy, based on a colloidal crystal‐templating method, utilizes nitrogenous dopamine as the precursor due to its unique properties, including self‐polymerization under mild alkaline conditions, coating onto various surfaces, a high carbonization yield, and well‐preserved nitrogen doping after heat treatment. The obtained NHPC‐3D possesses a high surface area of 1056 m2 g?1, a large pore volume of 2.56 cm3 g?1, and a high nitrogen content of 8.2 wt %. The NHPC‐3D is implemented as the electrode material of a supercapacitor and exhibits a specific capacitance as high as 252 F g?1 at a current density of 2 A g?1. The device also shows a high capacitance retention of 75.7 % at a higher current density of 20 A g?1 in aqueous electrolyte due to a sufficient surface area for charge accommodation, reversible pseudocapacitance, and minimized ion‐transport resistance, as a result of the advantageous interconnected hierarchical porous texture. These results showcase NHPC‐3D as a promising candidate for electrode materials in supercapacitors. 相似文献
2.
Guiyin Xu Bing Ding Ping Nie Laifa Shen Jie Wang Prof. Xiaogang Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(37):12306-12312
Porous nitrogen‐doped carbon nanotubes (PNCNTs) with a high specific surface area (1765 m2 g?1) and a large pore volume (1.28 cm3 g?1) have been synthesized from a tubular polypyrrole (T‐PPY). The inner diameter and wall thickness of the PNCNTs are about 55 nm and 22 nm, respectively. This material shows extremely promising properties for both supercapacitors and for encapsulating sulfur as a superior cathode material for high‐performance lithium–sulfur (Li‐S) batteries. At a current density of 0.5 A g?1, PNCNT presents a high specific capacitance of 210 F g?1, as well as excellent cycling stability at a current density of 2 A g?1. When the S/PNCNT composite was tested as the cathode material for Li‐S batteries, the initial discharge capacity was 1341 mAh g?1 at a current rate of 1 C and, even after 50 cycles at the same rate, the high reversible capacity was retained at 933 mAh g?1. The promising electrochemical energy‐storage performance of the PNCNTs can be attributed to their excellent conductivity, large surface area, nitrogen doping, and unique pore‐size distribution. 相似文献
3.
MnO2 Nanosheets Grown on Nitrogen‐Doped Hollow Carbon Shells as a High‐Performance Electrode for Asymmetric Supercapacitors
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Lei Li Rumin Li Shili Gai Prof. Shujiang Ding Fei He Prof. Milin Zhang Prof. Piaoping Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(19):7119-7126
A hierarchical hollow hybrid composite, namely, MnO2 nanosheets grown on nitrogen‐doped hollow carbon shells (NHCSs@MnO2), was synthesized by a facile in situ growth process followed by calcination. The composite has a high surface area (251 m2g?1) and mesopores (4.5 nm in diameter), which can efficiently facilitate transport during electrochemical cycling. Owing to the synergistic effect of NHCSs and MnO2, the composite shows a high specific capacitance of 306 F g?1, good rate capability, and an excellent cycling stability of 95.2 % after 5000 cycles at a high current density of 8 A g?1. More importantly, an asymmetric supercapacitor (ASC) assembled by using NHCSs@MnO2 and activated carbon as the positive and negative electrodes exhibits high specific capacitance (105.5 F g?1 at 0.5 A g?1 and 78.5 F g?1 at 10 A g?1) with excellent rate capability, achieves a maximum energy density of 43.9 Wh kg?1 at a power density of 408 W kg?1, and has high stability, whereby the ASC retains 81.4 % of its initial capacitance at a current density of 5 A g?1 after 4000 cycles. Therefore, the NHCSs@MnO2 electrode material is a promising candidate for future energy‐storage systems. 相似文献
4.
Heteroatom‐Doped Porous Carbon Nanosheets: General Preparation and Enhanced Capacitive Properties
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Xiaodong Hao Jie Wang Bing Ding Laifa Shen Yunling Xu Ya Wang Zhi Chang Hui Dou Xiangjun Lu Prof. Xiaogang Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(46):16668-16674
High‐performance electrical double‐layer capacitors (EDLCs) require carbon electrode materials with high specific surface area, short ion‐diffusion pathways, and outstanding electrical conductivity. Herein, a general approach combing the molten‐salt method and chemical activation to prepare N‐doped carbon nanosheets with high surface area (654 m2 g?1) and adjustable porous structure is presented. Owing to their structural features, the N‐doped carbon nanosheets exhibited superior capacitive performance, demonstrated by a maximum capacitance of 243 F g?1 (area‐normalized capacitance up to 37 μF cm?2) at a current density of 0.5 A g?1 in aqueous electrolyte, high rate capability (179 F g?1 at 20 A g?1), and excellent cycle stability. This method provides a new route to prepare porous and heteroatom‐doped carbon nanosheets for high‐performance EDLCs, which could also be extended to other polymer precursors and even waste biomass. 相似文献
5.
Synthesis of Hierarchically Porous Sandwich‐Like Carbon Materials for High‐Performance Supercapacitors
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Yiju Li Dr. Chaoji Chen Tingting Gao Dr. Dongming Zhang Dr. Xiaomei Huang Yue Pan Dr. Ke Ye Dr. Kui Cheng Dr. Dianxue Cao Dr. Guiling Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(47):16863-16871
For the first time, hierarchically porous carbon materials with a sandwich‐like structure are synthesized through a facile and efficient tri‐template approach. The hierarchically porous microstructures consist of abundant macropores and numerous micropores embedded into the crosslinked mesoporous walls. As a result, the obtained carbon material with a unique sandwich‐like structure has a relatively high specific surface (1235 m2 g?1), large pore volume (1.30 cm3 g?1), and appropriate pore size distribution. These merits lead to a comparably high specific capacitance of 274.8 F g?1 at 0.2 A g?1 and satisfying rate performance (87.7 % retention from 1 to 20 A g?1). More importantly, the symmetric supercapacitor with two identical as‐prepared carbon samples shows a superior energy density of 18.47 Wh kg?1 at a power density of 179.9 W kg?1. The asymmetric supercapacitor based on as‐obtained carbon sample and its composite with manganese dioxide (MnO2) can reach up to an energy density of 25.93 Wh kg?1 at a power density of 199.9 W kg?1. Therefore, these unique carbon material open a promising prospect for future development and utilization in the field of energy storage. 相似文献
6.
In Situ Growth of MnO2 Nanosheets on N‐Doped Carbon Nanotubes Derived from Polypyrrole Tubes for Supercapacitors
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Nitrogen‐doped porous carbon nanotubes@MnO2 (N‐CNTs@MnO2) nanocomposites are prepared through the in situ growth of MnO2 nanosheets on N‐CNTs derived from polypyrrole nanotubes (PNTs). Benefiting from the synergistic effects between N‐CNTs (high conductivity and N doping level) and MnO2 nanosheets (high theoretical capacity), the as‐prepared N‐CNTs@MnO2‐800 nanocomposites show a specific capacitance of 219 F g?1 at a current density of 1.0 A g?1, which is higher than that of pure MnO2 nanosheets (128 F g?1) and PNTs (42 F g?1) in 0.5 m Na2SO4 solution. Meanwhile, the capacitance retention of 86.8 % (after 1000 cycles at 10 A g?1) indicates an excellent electrochemical performance of N‐CNTs@MnO2 prepared in this work. 相似文献
7.
A Microwave Synthesis of Mesoporous NiCo2O4 Nanosheets as Electrode Materials for Lithium‐Ion Batteries and Supercapacitors
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Anjon Kumar Mondal Dr. Dawei Su Shuangqiang Chen Katja Kretschmer Xiuqiang Xie Prof. Hyo‐Jun Ahn Prof. Guoxiu Wang 《Chemphyschem》2015,16(1):169-175
A facile microwave method was employed to synthesize NiCo2O4 nanosheets as electrode materials for lithium‐ion batteries and supercapacitors. The structure and morphology of the materials were characterized by X‐ray diffraction, field‐emission scanning electron microscopy, transmission electron microscopy and Brunauer–Emmett–Teller methods. Owing to the porous nanosheet structure, the NiCo2O4 electrodes exhibited a high reversible capacity of 891 mA h g?1 at a current density of 100 mA g?1, good rate capability and stable cycling performance. When used as electrode materials for supercapacitors, NiCo2O4 nanosheets demonstrated a specific capacitance of 400 F g?1 at a current density of 20 A g?1 and superior cycling stability over 5000 cycles. The excellent electrochemical performance could be ascribed to the thin porous structure of the nanosheets, which provides a high specific surface area to increase the electrode–electrolyte contact area and facilitate rapid ion transport. 相似文献
8.
Man Jiang Jingli Zhang Lingbao Xing Jin Zhou Hongyou Cui Weijiang Si Shuping Zhuo 《中国化学》2016,34(11):1093-1102
Porous carbons (PC) were prepared from a waste biomass named chestnut shell via a two‐step method involving carbonization and KOH activation. The morphology, pore structure and surface chemical properties were investigated by scanning electron microscopy (SEM), N2 sorption, Raman spectroscopy, X‐ray diffraction (XRD) and X‐ray photoelectron spectroscopy (XPS). The carbons have been evaluated as the electrode materials for supercapacitors by a two‐electrode system in 6 mol/L KOH electrolyte. Benefiting from the porous texture, high surface area and high oxygen content, the PCs derived from chestnut shell have exhibited high specific capacitance of 198.2 (PC‐1), 217.2 (PC‐2) and 238.2 F·g?1 (PC‐3) at a current density of 0.1 A·g?1, good rate capability of 55.7%, 56.6% and 54.9% in a range of 0.1–20 A·g?1 and high energy density of 5.6, 6.1 and 6.7 Wh·kg?1, respectively. This is believed to be due to electric double layer capacitance induced by the abundant micropores and extra pseudo‐capacitance generated by oxygen‐containing groups. At a power density of 9000 Wh·kg?1, the energy density is 3.1, 3.5 and 3.7 Wh·kg?1 for PC‐1, PC‐2 and PC‐3, respectively, demonstrating the potential of the carbons derived from chestnut shells in energy storage devices. 相似文献
9.
Sodium‐Doped Mesoporous Ni2P2O7 Hexagonal Tablets for High‐Performance Flexible All‐Solid‐State Hybrid Supercapacitors
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Dr. Chengzhen Wei Cheng Cheng Shanshan Wang Yazhou Xu Jindi Wang Prof. Huan Pang 《化学:亚洲杂志》2015,10(8):1731-1737
A simple hydrothermal method has been developed to prepare hexagonal tablet precursors, which are then transformed into porous sodium‐doped Ni2P2O7 hexagonal tablets by a simple calcination method. The obtained samples were evaluated as electrode materials for supercapacitors. Electrochemical measurements show that the electrode based on the porous sodium‐doped Ni2P2O7 hexagonal tablets exhibits a specific capacitance of 557.7 F g?1 at a current density of 1.2 A g?1. Furthermore, the porous sodium‐doped Ni2P2O7 hexagonal tablets were successfully used to construct flexible solid‐state hybrid supercapacitors. The device is highly flexible and achieves a maximum energy density of 23.4 Wh kg?1 and a good cycling stability after 5000 cycles, which confirms that the porous sodium‐doped Ni2P2O7 hexagonal tablets are promising active materials for flexible supercapacitors. 相似文献
10.
Compact Coupled Graphene and Porous Polyaryltriazine‐Derived Frameworks as High Performance Cathodes for Lithium‐Ion Batteries
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Prof. Yuezeng Su Yuxin Liu Dr. Ping Liu Dr. Dongqing Wu Dr. Xiaodong Zhuang Prof. Fan Zhang Prof. Xinliang Feng 《Angewandte Chemie (International ed. in English)》2015,54(6):1812-1816
It is highly desirable to develop electroactive organic materials and their derivatives as green alternatives of cathodes for sustainable and cost‐effective lithium‐ion batteries (LIBs) in energy storage fields. Herein, compact two‐dimensional coupled graphene and porous polyaryltriazine‐derived frameworks with tailormade pore structures are fabricated by using various molecular building blocks under ionothermal conditions. The porous nanosheets display nanoscale thickness, high specific surface area, and strong coupling of electroactive polyaryltriazine‐derived frameworks with graphene. All these features make it possible to efficiently depress the dissolution of redox moieties in electrolytes and to boost the electrical conductivity of whole electrode. When employed as a cathode in LIBs, the two‐dimensional porous nanosheets exhibit outstanding cycle stability of 395 mAh g?1 at 5 A g?1 for more than 5100 cycles and excellent rate capability of 135 mAh g?1 at a high current density of 15 A g?1. 相似文献
11.
Zhao Wang Dr. Min Zhou Hao Chen Dr. Jingui Jiang Prof. Dr. Shiyou Guan 《化学:亚洲杂志》2014,9(10):2789-2797
A series of hierarchical activated mesoporous carbons (AMCs) were prepared by the activation of highly ordered, body‐centered cubic mesoporous phenolic‐resin‐based carbon with KOH. The effect of the KOH/carbon‐weight ratio on the textural properties and capacitive performance of the AMCs was investigated in detail. An AMC prepared with a KOH/carbon‐weight ratio of 6:1 possessed the largest specific surface area (1118 m2 g?1), with retention of the ordered mesoporous structure, and exhibited the highest specific capacitance of 260 F g?1 at a current density of 0.1 A g?1 in 1 M H2SO4 aqueous electrolyte. This material also showed excellent rate capability (163 F g?1 retained at 20 A g?1) and good long‐term electrochemical stability. This superior capacitive performance could be attributed to a large specific surface area and an optimized micro‐mesopore structure, which not only increased the effective specific surface area for charge storage but also provided a favorable pathway for efficient ion transport. 相似文献
12.
Anjon Kumar Mondal Dawei Su Dr. Ying Wang Shuangqiang Chen Prof. Guoxiu Wang 《化学:亚洲杂志》2013,8(11):2828-2832
Nickel oxide nanosheets have been successfully synthesized by a facile ethylene glycol mediated hydrothermal method. The morphology and crystal structure of the nickel oxide nanosheets were characterized by X‐ray diffraction, field‐emission SEM, and TEM. When applied as electrode materials for lithium‐ion batteries and supercapacitors, nickel oxide nanosheets exhibited a high, reversible lithium storage capacity of 1193 mA h g?1 at a current density of 500 mA g?1, an enhanced rate capability, and good cycling stability. Nickel oxide nanosheets also demonstrated a superior specific capacitance of 999 F g?1 at a current density of 20 A g?1 in supercapacitors. 相似文献
13.
One‐Step Pyro‐Synthesis of a Nanostructured Mn3O4/C Electrode with Long Cycle Stability for Rechargeable Lithium‐Ion Batteries
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Muhammad Hilmy Alfaruqi Dr. Jihyeon Gim Sungjin Kim Jinju Song Pham Tung Duong Jeonggeun Jo Dr. Joseph Paul Baboo Dr. Zhiliang Xiu Dr. Vinod Mathew Prof. Jaekook Kim 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(6):2039-2045
A nanostructured Mn3O4/C electrode was prepared by a one‐step polyol‐assisted pyro‐synthesis without any post‐heat treatments. The as‐prepared Mn3O4/C revealed nanostructured morphology comprised of secondary aggregates formed from carbon‐coated primary particles of average diameters ranging between 20 and 40 nm, as evidenced from the electron microscopy studies. The N2 adsorption studies reveal a hierarchical porous feature in the nanostructured electrode. The nanostructured morphology appears to be related to the present rapid combustion strategy. The nanostructured porous Mn3O4/C electrode demonstrated impressive electrode properties with reversible capacities of 666 mAh g?1 at a current density of 33 mA g?1, good capacity retentions (1141 mAh g?1 with 100 % Coulombic efficiencies at the 100th cycle), and rate capabilities (307 and 202 mAh g?1 at 528 and 1056 mA g?1, respectively) when tested as an anode for lithium‐ion battery applications. 相似文献
14.
Excellent Capacitive Performance of a Three‐Dimensional Hierarchical Porous Graphene/Carbon Composite with a Superhigh Surface Area
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Xue Jin Li Prof. Wei Xing Prof. Jin Zhou Prof. Gui Qiang Wang Prof. Shu Ping Zhuo Prof. Zi Feng Yan Prof. Qing Zhong Xue Prof. Shi Zhang Qiao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(41):13314-13320
Three‐dimensional hierarchical porous graphene/carbon composite was successfully synthesized from a solution of graphene oxide and a phenolic resin by using a facile and efficient method. The morphology, structure, and surface property of the composite were investigated intensively by a variety of means such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption, Raman spectroscopy, and Fourier transform infrared spectroscopy (FTIR). It is found that graphene serves as a scaffold to form a hierarchical pore texture in the composite, resulting in its superhigh surface area of 2034 m2g?1, thin macropore wall, and high conductivity (152 S m?1). As evidenced by electrochemical measurements in both EMImBF4 ionic liquid and KOH electrolyte, the composite exhibits ideal capacitive behavior, high capacitance, and excellent rate performance due to its unique structure. In EMImBF4, the composite has a high energy density of up to 50.1 Wh kg?1 and also possesses quite stable cycling stability at 100 °C, suggesting its promising application in high‐temperature supercapacitors. In KOH electrolyte, the specific capacitance of this composite can reach up to an unprecedented value of 186.5 F g?1, even at a very high current density of 50 A g?1, suggesting its prosperous application in high‐power applications. 相似文献
15.
Zhong Jie Zhang Peng Cui Xiang Ying Chen Jian Wei Liu 《Journal of Solid State Electrochemistry》2013,17(6):1749-1758
High-performance activated carbon for electrochemical double-layer capacitors (EDLC) has been prepared from cation exchange resin by carbonization and subsequent activation with KOH. The activation temperature has a key role in the determination of porous carbon possessing high surface areas, and large pore structures. The porous carbon activated at 700 °C (carbon-700-1:4) has high surface area (2236 m2?g?1) and large total pore volume (1.15 cm3?g?1), which also displays best capacitive performances due to its well-balanced micro- or mesoporosity distribution. In details, specific capacitances of the carbon-700-1:4 sample are 336.5 F?g?1 at a current density of 1 A?g?1 and 331.8 F?g?1 at 2 A?g?1. At high current density as 20 A?g?1, the retention of its specific capacitance is 68.4 %. The carbon-700-1:4 sample also exhibits high performance of energy density (46.7 Wh?kg?1) and long cycle stability (~8.9 % loss after 3,000 cycles). More importantly, due to the amount of waste ion-exchange resins increasing all over the world, the present synthetic method might be adopted to dispose them, producing high-performance porous carbons for EDLC electrode materials. 相似文献
16.
Conductive Microporous Covalent Triazine‐Based Framework for High‐Performance Electrochemical Capacitive Energy Storage
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Yajuan Li Shuanghao Zheng Xue Liu Pan Li Dr. Lei Sun Ruixia Yang Sen Wang Prof. Dr. Zhong‐Shuai Wu Prof. Dr. Xinhe Bao Prof. Dr. Wei‐Qiao Deng 《Angewandte Chemie (International ed. in English)》2018,57(27):7992-7996
Nitrogen‐enriched porous nanocarbon, graphene, and conductive polymers attract increasing attention for application in supercapacitors. However, electrode materials with a large specific surface area (SSA) and a high nitrogen doping concentration, which is needed for excellent supercapacitors, has not been achieved thus far. Herein, we developed a class of tetracyanoquinodimethane‐derived conductive microporous covalent triazine‐based frameworks (TCNQ‐CTFs) with both high nitrogen content (>8 %) and large SSA (>3600 m2 g?1). These CTFs exhibited excellent specific capacitances with the highest value exceeding 380 F g?1, considerable energy density of 42.8 Wh kg?1, and remarkable cycling stability without any capacitance degradation after 10 000 cycles. This class of CTFs should hold a great potential as high‐performance electrode material for electrochemical energy‐storage systems. 相似文献
17.
A three‐dimensional (3D) hierarchical MOF‐on‐reduced graphene oxide (MOF‐on‐rGO) compartment was successfully synthesized through an in situ reduced and combined process. The unique properties of the MOF‐on‐rGO compartment combining the polarity and porous features of MOFs with the high conductivity of rGO make it an ideal candidate as a sulfur host in lithium–sulfur (Li‐S) batteries. A high initial discharge capacity of 1250 mAh g?1 at a current density of 0.1 C (1.0 C=1675 mAh g?1) was reached using the MOF‐on‐rGO based electrode. At the rate of 1.0 C, a high specific capacity of 601 mAh g?1 was still maintained after 400 discharge–charge cycles, which could be ascribed to the synergistic effect between MOFs and rGO. Both the hierarchical structures of rGO and the polar pore environment of MOF retard the diffusion and migration of soluble polysulfide, contributing to a stable cycling performance. Moreover, the spongy‐layered rGO can buffer the volume expansion and contraction changes, thus supplying stable structures for Li‐S batteries. 相似文献
18.
Xiaoyan Li Kaikai Li Sicong Zhu Ke Fan Linlong Lyu Haimin Yao Yiyang Li Jinlian Hu Haitao Huang Yiu‐Wing Mai John B. Goodenough 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(19):6305-6309
The sodium‐ion battery is a promising battery technology owing to its low price and high abundance of sodium. However, the sluggish kinetics of sodium ion makes it hard to achieve high‐rate performance, therefore impairing the power density. In this work, a fiber‐in‐tube Co9S8‐carbon(C)/Co9S8 is designed with fast sodiation kinetics. The experimental and simulation analysis show that the dominating capacitance mechanism for the high Na‐ion storage performance is due to abundant grain boundaries, three exposed layer interfaces, and carbon wiring in the design. As a result, the fiber‐in‐tube hybrid anode shows a high specific capacity of 616 mAh g?1 after 150 cycles at 0.5 A g?1. At 1 A g?1, a capacity of ca. 451 mAh g?1 can be achieved after 500 cycles. More importantly, a high energy density of 779 Wh kg?1 and power density of 7793 W kg?1 can be obtained simultaneously. 相似文献
19.
Ahmed F. M. El‐Mahdy Ying‐Hui Hung Tharwat Hassan Mansoure Hsiao‐Hua Yu Tao Chen Shiao‐Wei Kuo 《化学:亚洲杂志》2019,14(9):1429-1435
In this paper we report the construction of a hollow microtubular triazine‐ and benzobisoxazole‐based covalent organic framework (COF) presenting a sponge‐like shell through a template‐free [3+2] condensation of the planar molecules 2,4,6‐tris(4‐formylphenyl)triazine (TPT‐3CHO) and 2,5‐diaminohydroquinone dihydrochloride (DAHQ‐2HCl). The synthesized COF exhibited extremely high crystallinity, a high surface area (ca. 1855 m2 g?1), and ultrahigh thermal stability. Interestingly, a time‐dependent study of the formation of the hollow microtubular COF having a sponge‐like shell revealed a transformation from initial ribbon‐like crystallites into a hollow tubular structure, and confirmed that the hollow nature of the synthesized COF was controlled by inside‐out Ostwald ripening, while the non‐interaction of the crystallites on the outer surface was responsible for the sponge‐like surface of the tubules. This COF exhibited significant supercapacitor performance: a high specific capacitance of 256 F g?1 at a current density of 0.5 A g?1, excellent cycling stability (98.8 % capacitance retention over 1850 cycles), and a high energy density of 43 Wh kg?1. Such hollow structural COFs with sponge‐like shells appear to have great potential for use as high‐performance supercapacitors in energy storage applications. 相似文献
20.
Binary transition metal selenides have been more promising than single transition metal selenides as anode materials for sodium‐ion batteries (SIBs). However, the controlled synthesis of transition metal selenides, especially those derived from metal‐organic‐frameworks with well‐controlled structure and morphology is still challenging. In this paper, highly porous NiCoSe4@NC composite microspheres were synthesized by simultaneous carbonization and selenization of a Ni?Co‐based metal‐organic framework (NiCo‐MOF) and characterized by scanning electron microscopy, transition electron microscopy, X‐Ray diffraction, X‐Ray photoelectron spectroscopy and electrochemical techniques. The rationally engineered NiCoSe4@NC composite exhibits a capacity of 325 mAh g?1 at a current density of 1 A g?1, and 277.8 mAh g?1 at 10 A g?1. Most importantly, the NiCoSe4@NC retains a capacity of 293 mAh g?1 at 1 A g?1 after 1500 cycles, with a capacity decay rate of 0.025 % per cycle. 相似文献