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1.
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
2.
Songwei Gao Nü Wang Shuai Li Dianming Li Zhimin Cui Guichu Yue Jingchong Liu Xiaoxian Zhao Lei Jiang Yong Zhao 《Angewandte Chemie (International ed. in English)》2020,59(6):2465-2472
Multi‐wall Sn/SnO2@carbon hollow nanofibers evolved from SnO2 nanofibers are designed and programable synthesized by electrospinning, polypyrrole coating, and annealing reduction. The synthesized hollow nanofibers have a special wire‐in‐double‐wall‐tube structure with larger specific surface area and abundant inner spaces, which can provide effective contacting area of electrolyte with electrode materials and more active sites for redox reaction. It shows excellent cycling stability by virtue of effectively alleviating pulverization of tin‐based electrode materials caused by volume expansion. Even after 2000 cycles, the wire‐in‐double‐wall‐tube Sn/SnO2@carbon nanofibers exhibit a high specific capacity of 986.3 mAh g?1 (1 A g?1) and still maintains 508.2 mAh g?1 at high current density of 5 A g?1. This outstanding electrochemical performance suggests the multi‐wall Sn/SnO2@ carbon hollow nanofibers are great promising for high performance energy storage systems. 相似文献
3.
Dr. Anqiang Pan Ting Zhu Hao Bin Wu Prof. Xiong Wen Lou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(2):494-500
Nanosheet‐assembled hierarchical V2O5 hollow microspheres are successfully obtained from V‐glycolate precursor hollow microspheres, which in turn are synthesized by a simple template‐free solvothermal method. The structural evolution of the V‐glycolate hollow microspheres has been studied and explained by the inside‐out Ostwald‐ripening mechanism. The surface morphologies of the hollow microspheres can be controlled by varying the mixture solution and the solvothermal reaction time. After calcination in air, hierarchical V2O5 hollow microspheres with a high surface area of 70 m2 g?1 can be obtained and the structure is well preserved. When evaluated as cathode materials for lithium‐ion batteries, the as‐prepared hierarchical V2O5 hollow spheres deliver a specific discharge capacity of 144 mA h g?1 at a current density of 100 mA g?1, which is very close to the theoretical capacity (147 mA h g?1) for one Li+ insertion per V2O5. In addition, excellent rate capability and cycling stability are observed, suggesting their promising use in lithium‐ion batteries. 相似文献
4.
Junfei Duan Yongkang Wang Hongxing Li Donghai Wei Fang Wen Guanhua Zhang Piao Liu Lingjun Li Wei‐bing Zhang Zhaoyong Chen 《化学:亚洲杂志》2020,15(10):1613-1620
Heterostructure engineering of electrode materials, which is expected to accelerate the ion/electron transport rates driven by a built‐in internal electric field at the heterointerface, offers unprecedented promise in improving their cycling stability and rate performance. Herein, carbon nanotubes with Co9S8/ZnS heterostructures embedded in a N‐doped carbon framework (Co9S8/ZnS@NC) have been rationally designed via an in‐situ vapor chemical transformation strategy with the aid of thiophene, which not only acted as carbon source for the growth of carbon nanotubes but also as sulfur source for the sulfurization of metal Zn and Co. Density functional theory (DFT) calculation shows an about 3.24 eV electrostatic potential difference between ZnS and Co9S8, which results in a strong electrostatic field across the interface that makes electrons transfer from Co9S8 to the ZnS side. As expected, a stable cycling performance with reversible capacity of 411.2 mAh g?1 at 1000 mA g?1 after 300 cycles, excellent rate capability (324 mAh g?1 at 2000 A g?1) and a high percentage of pseudocapacitance contribution (87.5% at 2.2 mv/s) for lithium‐ion batteries (LIBs) are achieved. This work provides a possible strategy for designing multicomponent heterostructural materials for application in energy storage and conversion fields. 相似文献
5.
Nitrogen‐Doped Hollow Amorphous Carbon Spheres@Graphitic Shells Derived from Pitch: New Structure Leads to Robust Lithium Storage
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Qingtao Ma Prof. Dr. Luxiang Wang Dr. Wei Xia Prof. Dr. Dianzeng Jia Prof. Zongbin Zhao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(7):2339-2344
Nitrogen‐doped mesoporous hollow carbon spheres (NHCS) consisting of hybridized amorphous and graphitic carbon were synthesized by chemical vapor deposition with pitch as raw material. Treatment with HNO3 vapor was performed to incorporate oxygen‐containing groups on NHCS, and the resulting NHCS‐O showed excellent rate capacity, high reversible capacity, and excellent cycling stability when tested as the anode material in lithium‐ion batteries. The NHCS‐O electrode maintained a reversible specific capacity of 616 mAh g?1 after 250 cycles at a current rate of 500 mA g?1, which is an increase of 113 % compared to the pristine hollow carbon spheres. In addition, the NHCS‐O electrode exhibited a reversible capacity of 503 mAh g?1 at a high current density of 1.5 A g?1. The superior electrochemical performance of NHCS‐O can be attributed to the hybrid structure, high N and O contents, and rich surface defects. 相似文献
6.
Heng‐guo Wang Haidong Wang Zhenjun Si Qiang Li Qiong Wu Qi Shao Lanlan Wu Yu Liu Yinghui Wang Shuyan Song Hongjie Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(30):10310-10314
Bipolar redox organics have attracted interest as electrode materials for energy storage owing to their flexibility, sustainability and environmental friendliness. However, an understanding of their application in all‐organic batteries, let alone dual‐ion batteries (DIBs), is in its infancy. Herein, we propose a strategy to screen a variety of phthalocyanine‐based bipolar organics. The self‐polymerizable bipolar Cu tetraaminephthalocyanine (CuTAPc) shows multifunctional applications in various energy storage systems, including lithium‐based DIBs using CuTAPc as the cathode material, graphite‐based DIBs using CuTAPc as the anode material and symmetric DIBs using CuTAPc as both the cathode and anode materials. Notably, in lithium‐based DIBs, the use of CuTAPc as the cathode material results in a high discharge capacity of 236 mAh g?1 at 50 mA g?1 and a high reversible capacity of 74.3 mAh g?1 after 4000 cycles at 4 A g?1. Most importantly, a high energy density of 239 Wh kg?1 and power density of 11.5 kW kg?1 can be obtained in all‐organic symmetric DIBs. 相似文献
7.
Xianyong Wu Aaron Markir Lu Ma Yunkai Xu Heng Jiang Daniel P. Leonard Woochul Shin Tianpin Wu Jun Lu Xiulei Ji 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(36):12770-12775
The elemental sulfur electrode with Cu2+ as the charge carrier gives a four‐electron sulfur electrode reaction through the sequential conversion of S?CuS?Cu2S. The Cu‐S redox‐ion electrode delivers a high specific capacity of 3044 mAh g?1 based on the sulfur mass or 609 mAh g?1 based on the mass of Cu2S, the completely discharged product, and displays an unprecedently high potential of sulfur/metal sulfide reduction at 0.5 V vs. SHE. The Cu‐S electrode also exhibits an extremely low extent of polarization of 0.05 V and an outstanding cycle number of 1200 cycles retaining 72 % of the initial capacity at 12.5 A g?1. The remarkable utility of this Cu‐S cathode is further demonstrated in a hybrid cell that employs an Zn metal anode and an anion‐exchange membrane as the separator, which yields an average cell discharge voltage of 1.15 V, the half‐cell specific energy of 547 Wh kg?1 based on the mass of the Cu2S/carbon composite cathode, and stable cycling over 110 cycles. 相似文献
8.
Dr. Xuefeng Wang Yejing Li Zhaoruxin Guan Prof. Zhaoxiang Wang Liquan Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6465-6468
Low storage capacity and poor cycling stability are the main drawbacks of the electrode materials for sodium‐ion (Na‐ion) batteries, due to the large radius of the Na ion. Here we show that micro‐structured molybdenum disulfide (MoS2) can exhibit high storage capacity and excellent cycling and rate performances as an anode material for Na‐ion batteries by controlling its intercalation depth and optimizing the binder. The former method is to preserve the layered structure of MoS2, whereas the latter maintains the integrity of the electrode during cycling. A reversible capacity of 90 mAh g?1 is obtained on a potential plateau feature when less than 0.5 Na per formula unit is intercalated into micro‐MoS2. The fully discharged electrode with sodium alginate (NaAlg) binder delivers a high reversible capacity of 420 mAh g?1. Both cells show excellent cycling performance. These findings indicate that metal chalcogenides, for example, MoS2, can be promising Na‐storage materials if their operation potential range and the binder can be appropriately optimized. 相似文献
9.
One‐Pot Fabrication of Hierarchical Nanosheet‐Based TiO2–Carbon Hollow Microspheres for Anode Materials of High‐Rate Lithium‐Ion Batteries
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Zhaokui Jin Prof. Mu Yang Jingjing Wang Hongyi Gao Prof. Yunfeng Lu Prof. Ge Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(17):6031-6036
Hierarchical and hollow nanostructures have recently attracted considerable attention because of their fantastic architectures and tunable property for facile lithium ion insertion and good cycling stability. In this study, a one‐pot and unusual carving protocol is demonstrated for engineering hollow structures with a porous shell. Hierarchical TiO2 hollow spheres with nanosheet‐assembled shells (TiO2 NHS) were synthesized by the sequestration between the titanium source and 2,2′‐bipyridine‐5,5′‐dicarboxylic acid, and kinetically controlled etching in trifluoroacetic acid medium. In addition, annealing such porous nanostructures presents the advantage of imparting carbon‐doped functional performance to its counterpart under different atmospheres. Such highly porous structures endow very large specifics surface area of 404 m2 g?1 and 336 m2 g?1 for the as‐prepared and calcination under nitrogen gas. C/TiO2 NHS has high capacity of 204 mA h g?1 at 1 C and a reversible capacity of 105 mA h g?1 at a high rate of 20 C, and exhibits good cycling stability and superior rate capability as an anode material for lithium‐ion batteries. 相似文献
10.
Highly Concentrated Electrolyte towards Enhanced Energy Density and Cycling Life of Dual‐Ion Battery
Li Xiang Xuewu Ou Xingyong Wang Zhiming Zhou Xiang Li Yongbing Tang 《Angewandte Chemie (International ed. in English)》2020,59(41):17924-17930
Dual‐ion batteries (DIBs) have attracted much attention owing to their low cost, high voltage, and environmental friendliness. As the source of active ions during the charging/discharging process, the electrolyte plays a critical role in the performance of DIBs, including capacity, energy density, and cycling life. However, most used electrolyte systems based on the LiPF6 salt demonstrate unsatisfactory performance in DIBs. We have successfully developed a 7.5 mol kg?1 lithium bis(fluorosulfonyl)imide (LiFSI) in a carbonate electrolyte system. Compared with diluted electrolytes, this highly concentrated electrolyte exhibits several advantages: 1) enhanced intercalation capacity and cycling stability of the graphite cathode, 2) optimized structural stability of the Al anode, and 3) significantly increased battery energy density. A proof‐of‐concept DIB based on this concentrated electrolyte exhibits a discharge capacity of 94.0 mAh g?1 at 200 mA g?1 and 96.8 % capacity retention after 500 cycles. By counting both the electrode materials and electrolyte, the energy density of this DIB reaches up to ≈180 Wh kg?1, which is among the best performances of DIBs reported to date. 相似文献
11.
Dr. Md Mokhlesur Rahman Irin Sultana Dr. Tianyu Yang Dr. Zhiqiang Chen Dr. Neeraj Sharma Dr. Alexey M. Glushenkov Prof. Ying Chen 《Angewandte Chemie (International ed. in English)》2016,55(52):16059-16063
A simple, cost‐effective, and easily scalable molten salt method for the preparation of Li2GeO3 as a new type of high‐performance anode for lithium‐ion batteries is reported. The Li2GeO3 exhibits a unique porous architecture consisting of micrometer‐sized clusters (secondary particles) composed of numerous nanoparticles (primary particles) and can be used directly without further carbon coating which is a common exercise for most electrode materials. The new anode displays superior cycling stability with a retained charge capacity of 725 mAh g?1 after 300 cycles at 50 mA g?1. The electrode also offers excellent rate capability with a capacity recovery of 810 mAh g?1 (94 % retention) after 35 cycles of ascending steps of current in the range of 25–800 mA g?1 and finally back to 25 mA g?1. This work emphasizes the importance of exploring new electrode materials without carbon coating as carbon‐coated materials demonstrate several drawbacks in full devices. Therefore, this study provides a method and a new type of anode with high reversibility and long cycle stability. 相似文献
12.
Qiang Jiang Peixun Xiong Jingjuan Liu Zhen Xie Qinchao Wang Xiao‐Qing Yang Enyuan Hu Yu Cao Jie Sun Yunhua Xu Long Chen 《Angewandte Chemie (International ed. in English)》2020,59(13):5273-5277
Metal–organic framework cathodes usually exhibit low capacity and poor electrochemical performance for Li‐ion storage owing to intrinsic low conductivity and inferior redox activity. Now a redox‐active 2D copper–benzoquinoid (Cu‐THQ) MOF has been synthesized by a simple solvothermal method. The abundant porosity and intrinsic redox character endow the 2D Cu‐THQ MOF with promising electrochemical activity. Superior performance is achieved as a Li‐ion battery cathode with a high reversible capacity (387 mA h g?1), large specific energy density (775 Wh kg?1), and good cycling stability. The reaction mechanism is unveiled by comprehensive spectroscopic techniques: a three‐electron redox reaction per coordination unit and one‐electron redox reaction per copper ion mechanism is demonstrated. This elucidatory understanding sheds new light on future rational design of high‐performance MOF‐based cathode materials for efficient energy storage and conversion. 相似文献
13.
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
14.
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
15.
Dr. Chengzhen Wei Cheng Cheng Dr. Junhong Zhao Yan Wang Yanyan Cheng Yazhou Xu Prof. Weimin Du Prof. Huan Pang 《化学:亚洲杂志》2015,10(3):679-686
α‐NiS and β‐NiS hollow spheres were successfully synthesized via the Kirkendall effect under different hydrothermal conditions. The obtained α‐NiS and β‐NiS hollow spheres were evaluated as electrode materials for supercapacitors. Importantly, the α‐NiS hollow sphere electrode has a large specific capacitance (562.3 F g?1 at 0.60 A g?1) and good cycling property (maintaining about 97.5 % at 2.4 A g?1 after 1000 cycles). Furthermore, the as‐prepared α‐NiS and β‐NiS hollow spheres were successfully applied to construct electrochemical glucose sensors. Especially, the α‐NiS hollow spheres exhibit a good sensitivity (155 μA mM?1 cm?2), low detection limit (0.125 μM ), and a wide linear range. 相似文献
16.
Chuangwei Jiao Zumin Wang Xiaoxian Zhao Huan Wang Jing Wang Ranbo Yu Dan Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(4):1008-1013
Precisely carving of multi‐shelled manganese–cobalt oxide hollow dodecahedra (Co/Mn‐HD) with shell number up to three is achieved by a controlled calcination of the Mn‐doped zeolitic imidazolate framework ZIF‐67 precursor (Co/Mn‐ZIF). The unique multi‐shelled and polycrystalline structure not only provides a very large electrochemically active surface area (EASA), but also enhances the structural stability of the material. The residual C and N in the final structures might aid stability and increase their conductivity. When used in alkaline rechargeable battery, the triple‐shelled Co/Mn‐HD exhibits high electrochemical performance, reversible capacity (331.94 mAh g?1 at 1 Ag?1), rate performance (88 % of the capacity can be retained with a 20‐fold increase in current density), and cycling stability (96 % retention over 2000 cycles). 相似文献
17.
Huinan Guo Guishu Liu Mengying Wang Yan Zhang Weiqin Li Kai Chen Yafei Liu Mengyuan Yue Yijing Wang 《化学:亚洲杂志》2020,15(9):1493-1499
Sodium‐ion batteries (SIBs) based on flexible electrode materials are being investigated recently for improving sluggish kinetics and developing energy density. Transition metal selenides present excellent conductivity and high capacity; nevertheless, their low conductivity and serious volume expansion raise challenging issues of inferior lifespan and capacity fading. Herein, an in‐situ construction method through carbonization and selenide synergistic effect is skillfully designed to synthesize a flexible electrode of bone‐like CoSe2 nano‐thorn coated on porous carbon cloth. The designed flexible CoSe2 electrode with stable structural feature displays enhanced Na‐ion storage capabilities with good rate performance and outstanding cycling stability. As expected, the designed SIBs with flexible BL?CoSe2/PCC electrode display excellent reversible capacity with 360.7 mAh g?1 after 180 cycles at a current density of 0.1 A g?1. 相似文献
18.
Self‐Template Synthesis of Hybrid Porous Co3O4–CeO2 Hollow Polyhedrons for High‐Performance Supercapacitors
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Prof. Chengzhen Wei Kangfei Liu Jing Tao Xiaoting Kang Haiyan Hou Cheng Cheng Prof. Daojun Zhang 《化学:亚洲杂志》2018,13(1):111-117
In this work, hybrid porous Co3O4–CeO2 hollow polyhedrons have been successfully obtained via a simple cation‐exchange route followed by heat treatment. In the synthesis process, ZIF‐67 polyhedron frameworks are firstly prepared, which not only serve as a host for the exchanged Ce3+ ions but also act as the template for the synthesis of hybrid porous Co3O4–CeO2 hollow polyhedrons. When utilized as electrode materials for supercapacitors, the hybrid porous Co3O4–CeO2 hollow polyhedrons delivered a large specific capacitance of 1288.3 F g?1 at 2.5 A g?1 and a remarkable long lifespan cycling stability (<3.3 % loss after 6000 cycles). Furthermore, an asymmetric supercapacitor (ASC) device based on hybrid porous Co3O4–CeO2 hollow polyhedrons was assembled. The ASC device possesses an energy density of 54.9 W h kg?1, which can be retained to 44.2 W h kg?1 even at a power density of 5100 W kg?1, indicating its promising application in electrochemical energy storage. More importantly, we believe that the present route is a simple and versatile strategy for the preparation of other hybrid metal oxides with desired structures, chemical compositions and applications. 相似文献
19.
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
20.
Chunfeng Meng Tianhui Chen Chun Fang Yunhui Huang Pinfei Hu Yongli Tong Ting Bian Jiaojiao Zhang Zhaoxuan Wang Aihua Yuan 《化学:亚洲杂志》2019,14(23):4289-4295
Recently, carboxylate metal‐organic framework (MOF) materials were reported to perform well as anode materials for lithium‐ion batteries (LIBs); however, the presumed lithium storage mechanism of MOFs is controversial. To gain insight into the mechanism of MOFs as anode materials for LIBs, a self‐supported Cu‐TCNQ (TCNQ: 7,7,8,8‐tetracyanoquinodimethane) film was fabricated via an in situ redox routine, and directly used as electrode for LIBs. The first discharge and charge specific capacities of the self‐supported Cu‐TCNQ electrode are 373.4 and 219.4 mAh g?1, respectively. After 500 cycles, the reversible specific capacity of Cu‐TCNQ reaches 280.9 mAh g?1 at a current density of 100 mA g?1. Mutually validated data reveal that the high capacity is ascribed to the multiple‐electron redox conversion of both metal ions and ligands, as well as the reversible insertion and desertion of Li+ ions into the benzene rings of ligands. This work raises the expectation for MOFs as electrode materials of LIBs by utilizing multiple active sites and provides new clues for designing improved electrode materials for LIBs. 相似文献